Glossary Heaven

Every important term explained.

A

Attosecond

An attosecond is a very tiny unit of time that helps scientists measure ultra fast events like the movement of electrons in atoms.

attogram

An attogram is a very tiny unit of mass used in science to measure things much lighter than dust, like single molecules and nanoparticles.

Atomic mass unit

Atomic mass unit is a very small unit used to measure the mass of atoms and tiny particles in a clear and easy way.

Acre-Inch

An acre inch is a volume of water that covers one acre of land to a depth of one inch, used mainly to plan and measure farm irrigation.

Acre-Foot

An acre foot is a large volume unit used to measure big amounts of water, like in lakes or farms, making water planning and sharing easier to understand.

Attoliter

An attoliter is a very tiny unit of volume that helps scientists measure extremely small amounts of liquid, such as inside cells or in nanotechnology experiments.

Arpent

An arpent is an old French unit used to measure land size and sometimes distance, mostly found today in old maps and land records in places with French history.

Acre (US Survey)

The acre (US survey) is a land area unit used in American surveying, slightly larger than a regular acre, helpful for mapping and old property records.

Are

An are is a metric unit for measuring land area, useful for understanding the size of gardens, fields, and small plots of land.

Arshin

Arshin is an old unit of length once used in Russia, about seventy one centimeters long, helpful for understanding old maps, books and history.

Arpent

Arpent is an old French unit used to measure land length and land area, especially in places like Quebec and Louisiana.

Attometer

An attometer is an extremely tiny unit of length used in science to measure things much smaller than atoms.

Angstrom

Learn what an angstrom is, why scientists use it, and how it helps measure extremely small things like atoms and light wavelengths in a simple way.

Astronomical unit

An astronomical unit is the average distance from Earth to the Sun, used by scientists to measure huge spaces in our solar system in a simple way.

Acre (ac)

An acre is a land area unit used for farms and property, and this guide explains its meaning, history, conversions, and common questions in very simple words.

Area

Area tells how much flat space a shape covers, and helps us measure land, rooms, maps, and more in units like square meters, square feet, and acres.

B

Barn

Learn what a barn unit is in physics, how small it is, and why scientists use it to measure area.

Barleycorn

Learn what a barleycorn is, how long it is, how it began as a grain based measure, and why it still matters for shoe sizes today.

Byte (B)

A byte is a small unit for measuring digital information that most often means 8 bits and is used to show the size of files, memory and storage.

Bit (bit)

A bit is the smallest unit of digital information and shows a simple choice like yes or no or 0 or 1 in computers.

BTU

BTU is a unit that measures heat energy, helping people compare heating and cooling power for things like heaters, air conditioners, and fuel use.

Bar (bar)

Learn what the bar unit is, how it measures pressure, where it is used, and how to change it into other common pressure units.

C

Calorie (nutritional)

A nutritional Calorie is a unit that shows how much energy food gives your body so you know how much fuel you get when you eat or drink.

Centimeter of Water (cmH₂O)

Centimeter of water is a small pressure unit that compares pressure to the weight of a short column of water and is often used in medicine and engineering.

Centimeter per Second (cm/s)

Centimeter per second is a small metric unit that shows how many centimeters something moves in one second, useful for measuring slow speeds in science.

Centimeter per Minute (cm/min)

Centimeter per minute is a small speed unit that shows how many centimeters something moves in one minute.

Centimeter per Hour (cm/h)

Centimeter per hour is a very small speed unit that shows how many centimeters something moves in one hour, useful for very slow movements or gentle flows.

centigram

A centigram is a very small metric unit for measuring mass, used to show tiny weights in science, maths and some product labels.

Cord

A cord is a standard size stack of firewood that helps people measure and trade wood in a clear and fair way.

Cup (Uk)

The cup (UK) is a cooking volume unit used in older British recipes, equal to half an imperial pint or about 284 millilitres.

Cup (Metric)

A metric cup is a simple way to measure kitchen liquids and dry foods, and it is usually set to 250 milliliters in many countries.

Centiliter

A centiliter is a small metric unit for measuring liquid volume, equal to one hundredth of a liter or ten milliliters.

Cubic Decimeter

A cubic decimeter is a metric unit for measuring volume, equal to one liter, and it helps compare the size of liquids and boxes in a clear way.

Cubic Inch

A cubic inch measures how much space something takes up inside. It is used mainly in the United States for volumes like engine size and small containers.

Cubic Foot

A cubic foot is a unit that measures space or volume, based on a cube that is one foot long, one foot wide, and one foot high.

Cubic Yard

A cubic yard is a unit that measures how much space something fills and is often used for soil, concrete and other large loose materials in building and gardening.

Cubic Mile

A cubic mile is a very large unit for measuring volume, equal to the space inside a cube that is one mile long, one mile wide, and one mile high.

Cuerda

A cuerda is a land area unit used mainly in Puerto Rico, close to an acre, helpful for measuring farms and property size.

Circular Mil

Learn what a circular mil is, how it measures wire size, and how to convert it to other area units in simple steps.

Circular Inch

A circular inch is an area unit for round shapes equal to the area of a circle with a 1 inch diameter, used mainly in wiring and engineering.

Chi

Chi is a traditional Chinese unit of length that helps measure things like cloth, rooms, and furniture in an easy way.

Cable

A cable is a sea distance unit used by sailors, helpful for reading nautical charts and turning ship lengths into easy numbers for safe navigation.

Cubit

A cubit is an old length unit based on the distance from a person’s elbow to fingertip, useful for understanding ancient buildings, maps, and history texts.

Chain

Chain is a unit for measuring length in land and map work, equal to 66 feet or about 20 meters, still useful for fields and property lines.

Calorie

A calorie is a unit that measures energy, often used to show how much energy food gives your body and how much energy things use.

Century

A century is a unit of time that equals 100 years and helps us talk about history, ages, and long periods in a simple way.

Carat

A carat is a unit used to measure the weight of gemstones like diamonds and it helps buyers compare size and value in a clear and simple way.

Cubic Nanometer (nm³)

A cubic nanometer is a very tiny unit used to measure extremely small volumes, like the space taken up by atoms and molecules in science and nanotechnology.

Cubic Micrometer (µm³)

Learn what a cubic micrometer is, how tiny it is, and how to change it into other volume units with simple examples and easy steps.

Cubic Millimeter (mm³)

A cubic millimeter is a very small unit for measuring volume, useful for tiny drops of liquid or small solid parts in science, medicine, and engineering.

Cubic Centimeter (cm³)

A cubic centimeter is a small unit for measuring volume, equal to one milliliter, and it helps us describe the size of liquids and solid objects in everyday life.

Cubic Kilometer (km³)

A cubic kilometer is a very large unit of volume used to measure things like oceans, big lakes and ice sheets, and this guide explains it in clear and simple steps.

Cubic Meter (m³)

A cubic meter is a metric unit that measures how much space something takes up in three dimensions, like the inside space of a big box or tank.

Celsius (°C)

Learn what Celsius means, how we use it to measure temperature, and see easy examples to understand cold and hot in everyday life.

Centimeter

A centimeter is a small unit that measures length in the metric system and helps you measure everyday objects like pencils, books, and phone screens.

D

Sidereal Day

A sidereal day is the time Earth needs to turn once in relation to distant stars, a bit less than 24 hours, and it is very important in astronomy.

Deuteron mass

Deuteron mass tells us how heavy the nucleus of heavy hydrogen is and helps scientists understand atoms, energy and nuclear reactions.

dalton

A dalton is a very small unit used to measure the mass of atoms and molecules, which helps scientists compare how heavy or light tiny particles are.

decigram

A decigram is a small metric unit for measuring mass that helps compare tiny amounts of things like spices, powders or medicine in a clear and simple way.

dekagram

A dekagram is a metric unit of mass equal to ten grams that helps measure small weights like food portions and recipe ingredients in a clear and simple way.

Dram

A dram is a small old unit for weight and liquid volume, useful for understanding old recipes, medicine doses and how people once measured tiny amounts.

Decistere

A decistere is a metric unit of volume equal to one tenth of a stere, mainly used in the past to measure stacked firewood and other bulky materials.

Dekastere

A dekastere is a metric unit of volume that equals ten cubic meters, often used to measure large stacks of firewood.

Dessertspoon (Uk)

A dessertspoon UK is a small volume unit used in cooking, equal to 10 millilitres, sitting between a teaspoon and a tablespoon.

Dessertspoon (Us)

A US dessertspoon is a cooking unit for volume that equals 2 teaspoons and helps measure medium amounts of ingredients in simple recipes.

Drop

A drop is a very small amount of liquid used to measure things like medicine, usually counted in drops instead of with a spoon.

Deciliter

A deciliter is a small metric unit for liquid volume, equal to one tenth of a liter, useful in cooking, science and nutrition labels.

Dekaliter

A dekaliter is a metric unit for measuring how much space a liquid or gas takes up, and it is exactly the same as 10 liters.

Decameter

A decameter is a metric length unit used to measure things that are about the size of a small field or building, equal to ten meters.

Decimeter

A decimeter is a metric unit for measuring length that is one tenth of a meter and helps describe sizes that are bigger than centimeters but smaller than full meters.

Data

Data is information that computers store and use, measured in units like bits and bytes, and it powers apps, games, videos, messages, and almost everything done online.

Decade

A decade is a time unit that means ten years and it helps us talk about history, age and long term plans in a clear and simple way.

Day

A day is a unit of time that usually means 24 hours, used to plan our lives, mark dates, and measure how long things take.

E

Earth’s Velocity

Earth’s velocity tells us how fast our planet moves when it spins on its axis and travels around the Sun and through the galaxy.

Earth’s mass

Earths mass is a very large unit that tells how heavy our planet is and helps scientists compare the size of other planets to Earth.

Electron mass (rest)

Learn what electron rest mass means, why it matters in science, and how it is used as a tiny unit of mass in physics and chemistry.

exagram

An exagram is a very large metric unit for measuring mass that equals one billion billion grams and is mainly used in science to describe huge objects.

Exaliter

An exaliter is a very large volume unit equal to one quintillion 1 000 000 000 000 000 000 liters, used to describe extremely huge amounts of liquid.

Electron Cross Section

Electron cross section tells how likely an electron is to hit or interact with something and helps scientists understand beams, radiation, plasmas and many other physical processes.

Ell

Learn what an ell is, how long it was in different countries, and how to convert this old cloth measuring unit into modern units like meters and feet.

Exameter

An exameter is a very large distance unit equal to one billion billion meters, used to describe huge space distances in science and astronomy.

Exbibyte (EiB)

An exbibyte is a very large unit for measuring digital data size, used to describe giant storage like data centers and big cloud services.

Exabyte (EB)

An exabyte is a very large unit for measuring digital data size, used to describe huge amounts of information in data centers and across the whole internet.

Electronvolt

An electronvolt is a tiny unit of energy used in physics to measure the energy of electrons, atoms and particles, helping scientists describe events inside atoms and high energy experiments.

Energy

Energy is the power to do work or cause change, like moving things, heating, or lighting, and it helps us understand how machines, people, and nature work.

F

Foot-pound (ft·lbf)

A foot-pound ft·lbf is a unit that measures how much work or energy is used when a force moves something through a distance in feet.

Foot per Minute (ft/min)

Foot per minute is a speed unit that tells how many feet something moves in one minute, so it helps you understand slow and medium speeds in a simple way.

Foot per Hour (ft/h)

Foot per hour is a very slow speed unit that tells how many feet something moves in one hour, useful for simple learning and a few special technical uses.

Fortnight

A fortnight is a time unit equal to two weeks, useful for understanding dates, pay periods, and schedules in many English speaking countries.

Femtosecond

A femtosecond is a very tiny slice of time that helps scientists measure super fast events like light movement and chemical reactions.

femtogram

A femtogram is a very small unit for measuring mass used in science, it helps describe the weight of extremely tiny things like viruses and single particles.

Fluid Ounce (Uk)

A fluid ounce UK is a small liquid unit used in Britain to measure drinks and other liquids, and it helps you know how much liquid fits in a container.

Femtoliter

A femtoliter is a very tiny unit for measuring liquid volume that scientists use to describe things as small as cells and droplets inside your body.

Fathom

A fathom is a unit used to measure water depth, equal to six feet, and it helps sailors, divers and fishers know how deep the water is.

Foot (US Survey)

The foot US survey is an old American length unit used in land maps and surveying, slightly longer than the international foot that most people use today.

Furlong

A furlong is an old unit for measuring length mostly used in horse racing and equals one eighth of a mile or about 201 meters.

Femtometer

A femtometer is a unit of length for very tiny distances used to measure things like atomic nuclei and particles inside atoms.

Feet per Second (ft/s)

Feet per second ft/s is a speed unit that tells how many feet something travels in one second, useful for physics, sports, and everyday motion.

Fahrenheit (°F)

Learn what Fahrenheit is, how this temperature scale works, where it is used today, and how to convert it to and from Celsius with simple examples.

Feet

Feet are a common unit of length used to measure how long or tall something is, especially in the United States and a few other countries.

G

Gigaton

A gigaton is a huge unit of mass that equals one billion metric tons, often used to measure things like ice loss and carbon pollution on Earth.

Gigawatt-hour (GWh)

A gigawatt hour is a large unit of energy that shows how much electricity is used or made when one billion watts run for one hour.

Gigajoule (GJ)

A gigajoule is a big unit for measuring energy that helps us describe large amounts of power, heat, or fuel in an easy and clear way.

Gigapascal (GPa)

A gigapascal GPa is a very large unit of pressure used in science and engineering, helpful for measuring how strong materials are under huge forces.

gerah (Biblical Hebrew)

Learn what the gerah is, an ancient Bible unit for weight and money, how big it was, and how it compares to grams and modern money.

gamma

Gamma is an old unit used to measure how strong a magnetic field is, and today it matches the modern unit called the nanotesla.

gigagram

A gigagram is a very large metric unit of mass that equals one billion grams and helps measure the weight of huge things like cities waste or big water supplies.

Gill (Uk)

The UK gill is a small old measurement for liquid volume, mostly for drinks, equal to one quarter of a pint, and helps compare recipes and bar measures.

Gill (Us)

A gill (US) is a small liquid volume unit used mainly for measuring drinks, equal to 4 US fluid ounces or about 118 milliliters.

Gigaliter

A gigaliter is a very large unit for measuring volume, often used to describe big amounts of water like lakes, dams and city water use.

Gaz

Gaz is an old unit for measuring length, used in Asia, similar to a yard, and still used in land and cloth deals in some countries.

Gigameter

A gigameter is a very large unit for measuring long distances in space, helping scientists describe billions of meters in a simple way.

Gibibyte (GiB)

A gibibyte GiB is a computer data unit that measures digital storage using powers of 2 and helps explain real memory and disk space more exactly.

Gigabyte (GB)

A gigabyte is a unit for measuring digital data, often used to show how much storage space a device or file has.

Gigabit (Gbit)

A gigabit is a unit for digital data, equal to one billion bits, often used to show how fast internet connections and networks can move information.

Grain

A grain is a very small unit of weight used to measure things like bullets, arrows, and medicine, and it helps compare tiny amounts in a clear way.

Gram

A gram is a small unit of mass used to measure how heavy something is, especially food, medicine and science tools.

Gallon (gal)

A gallon is a unit used to measure liquid volume, often for fuel and drinks, and this guide explains its types, history, and easy conversions.

H

Horsepower hour (hp·h)

Horsepower hour is a unit that shows how much work an engine does when it gives one horsepower of power for one full hour.

Hectopascal (hPa)

A hectopascal hPa is a unit of pressure used in weather reports, helping us measure how much air is pressing on the Earth at a place.

Sidereal Hour

A sidereal hour is a time unit used in astronomy that is slightly shorter than a normal hour and is based on Earth spinning once relative to distant stars.

Hebrew Bible

The Hebrew Bible is the sacred collection of Jewish books that tells the story of God, the people of Israel, and their laws, songs, and wisdom.

hundredweight (UK)

Learn what the UK hundredweight is, how heavy it is in pounds and kilograms, where it came from, and how to convert it to other weight units.

hundredweight (US)

The US hundredweight is a unit of weight equal to 100 pounds that helps measure large loads in farming, shipping, and industry.

hectogram

A hectogram is a metric unit of mass equal to 100 grams, useful for measuring food, small packages, and other everyday items in a simple way.

Hogshead

A hogshead is a very large barrel used in history and today to hold liquids like wine, beer, and whiskey, with size that changes by country and use.

Hundred-Cubic Foot

Hundred-cubic foot is a volume unit often used on gas and water bills to show how much space or fuel you used in a simple number.

Hectoliter

A hectoliter is a metric unit for volume, equal to 100 liters, often used for drinks like wine and beer, and for crops, in many countries.

Homestead

A homestead is a piece of land, often a farm with a house, that was given or sold to people under special laws in places like the United States and Canada.

Hand

A hand is a small unit of length used mainly to measure the height of horses and equals exactly 4 inches or about 10.16 centimeters.

Hectometer

A hectometer is a metric unit of length equal to 100 meters, useful for measuring medium distances like parts of roads or large fields.

Hour

An hour is a unit of time equal to 60 minutes, used worldwide to measure daily activities, work, travel, and schedules in a clear and simple way.

Hectare (ha)

A hectare is a unit used to measure land area, especially farms and fields, and helps compare the size of land in a clear and simple way.

I

Inch of Water (inH₂O)

Inch of water is a small pressure unit that shows how strongly a short column of water pushes on a surface.

Inch of Mercury (inHg)

Inch of mercury inHg is a pressure unit that shows how hard air or gas pushes, based on how high it can hold up a column of liquid mercury.

Imperial Quart (imp qt)

Learn what the imperial quart is, how it compares to liters and US quarts, and how to convert it using simple steps and clear examples.

Imperial Pint (imp pt)

An imperial pint is a British unit for measuring drinks, about half a liter, used mainly for beer, cider, and milk.

Imperial Gallon (imp gal)

Learn what the imperial gallon is, how it compares to the US gallon, and how to easily change imperial gallons into litres and other units.

Inch

An inch is a small unit for measuring length that helps you compare sizes, convert to centimeters, and understand everyday measurements like height, paper, and screen size.

J

Joule

A joule is the standard unit for measuring energy and work in science, used to describe how much energy is used, produced, or stored.

K

Kiloelectronvolt (keV)

A kiloelectronvolt is a small unit of energy that scientists use to measure very tiny energies, such as X rays, gamma rays, and other particle energies.

Kilowatt-second (kWs)

Learn what a kilowatt second is, how it links to joules and kilowatt hours, and how to convert this energy unit in everyday situations.

Kilowatt-hour (kWh)

A kilowatt hour is a unit that shows how much electrical energy is used or made over one hour, and it is what power companies use on your energy bill.

Kilojoule (kJ)

A kilojoule is a unit that measures energy and helps you understand how much power food, machines, and daily activities use.

Kilonewton per Square Meter (kN/m²)

Kilonewton per square meter is a metric unit that measures how much force presses on each square meter of area and is useful for pressure and strength calculations.

KSI (ksi)

KSI is a unit that measures how much force presses on an area, often used to show how strong metals and building parts are.

Kilopascal (kPa)

Learn what the kilopascal kPa is, how this pressure unit works, simple conversions, and where it is used in everyday life and science.

kiloton (metric)

A kiloton metric is a large unit of mass used to measure very heavy things like ships and big loads of goods equal to one million kilograms.

kip

A kip is a unit of force that equals one thousand pounds of force and is mainly used by engineers to measure very large loads on buildings and bridges.

kilopound

A kilopound is a unit used in engineering to measure large forces, equal to one thousand pounds of force.

kilogram-force square second/meter

Kilogram force square second per meter is an old unit of mass that links force, time, and distance, mainly used in older physics and engineering texts.

Kiloliter

A kiloliter is a metric unit for measuring large amounts of liquid, equal to 1,000 liters, useful for water tanks, fuel storage, and big containers.

Kos

Kos is an old South Asian unit of distance. Learn its meaning, size in kilometers, history, and simple conversions.

Ken

Ken is a traditional Japanese length unit used to plan buildings and rooms, and this guide explains its meaning, size, history, and easy conversions.

Kibibyte (KiB)

A kibibyte KiB is a unit of digital data that equals 1024 bytes and helps show file sizes in a clear and exact way.

Kilobyte (kB)

A kilobyte is a unit for measuring digital data size, often used to show how much text, images, or other files a device can store.

Kilobit (kbit)

A kilobit is a small unit for counting digital data, often used for internet speed and small file sizes in computers and networks.

Kilocalorie

A kilocalorie is a unit of energy used mainly for food labels and nutrition, showing how much energy your body can get from eating or drinking something.

Knots (kn)

Knots are a speed unit used mainly in air and sea travel, helping pilots and sailors measure how fast they move across Earth.

Kilometers per Hour (km/h)

Kilometers per hour is a unit that tells you how many kilometers you travel in one hour so it is a common way to measure speed in everyday life.

Kilogram

Learn what a kilogram is, how we use it to measure mass, and how to convert it to grams and pounds in simple steps.

Kelvin (K)

Kelvin K is the main science unit for temperature, based on how hot or cold something is compared with absolute zero, the coldest possible temperature.

Kilometer

Kilometers are a metric unit used to measure long distances, like the length of roads, trips, and maps, helping us compare and convert distances easily around the world.

L

Line

A line is a very small old unit of length that was used in printing, watchmaking, and other crafts, and can be converted to inches and millimeters.

League

A league is an old unit for measuring long distances on land or sea, usually about three miles, once common in travel, maps, and adventure stories.

Link

A link is an old unit of length once used in land surveying, helpful today for reading historic maps and changing old measurements into modern units.

Pound

A pound is a unit used to measure weight or mass, mainly in the United States and United Kingdom, and is helpful for understanding body weight, food, and many objects.

Liter (L)

A liter is a metric unit for measuring how much space a liquid or gas takes up and it is used every day for drinks, fuel, and many other things.

Light Year

A light year is a way to measure huge distances in space by how far light travels in one year, making star and galaxy distances easier to understand.

Length

Length is how long something is from one end to the other.

M

Megaton

A megaton is a very large unit used to measure the power of huge explosions, equal to the energy from one million tons of TNT.

Megaelectronvolt (MeV)

A megaelectronvolt is a small unit of energy used to measure very tiny energies in atoms, radiation, and particles in physics and medicine.

Mega BTU (MBtu)

Mega BTU, written as MBtu, is a unit that measures a large amount of heat energy used in heating, cooling and fuel calculations.

Megawatt-hour (MWh)

A megawatt-hour MWh is a unit that shows how much electrical energy is used or made when one million watts run for one hour.

Megajoule (MJ)

A megajoule is a unit for measuring energy that equals one million joules and helps compare things like fuel, electricity, and food energy in a clear way.

Millimeter of Water (mmH₂O)

Millimeter of water is a small unit for measuring pressure, based on the pressure made by a water column that is one millimeter high.

Millimeter of Mercury (mmHg)

Learn what millimeter of mercury mmHg means, how it measures pressure, and why doctors still use it for blood pressure today.

Megapascal (MPa)

Learn what a megapascal is, how it measures pressure and strength, and how to convert MPa into other common units like bar and psi in simple steps.

Mile per Second (mi/s)

Mile per second is a very fast speed unit that tells how many miles something travels in one second, useful for science and space ideas.

Mile per Minute (mi/min)

Mile per minute is a speed unit that shows how many miles something travels in one minute and it helps compare speeds in travel and transport.

Millimeter per Second (mm/s)

Millimeter per second is a small speed unit that tells how many millimeters something moves in one second.

Millimeter per Minute (mm/min)

Millimeter per minute is a speed unit that tells how many millimeters something moves or changes in one minute, useful for slow and precise motions.

Millimeter per Hour (mm/h)

Millimeter per hour is a speed unit that shows how many millimeters something moves or changes in one hour, often used for rain, drip rates, and slow movements.

Meter per Minute (m/min)

Meter per minute is a simple way to show how many meters something moves in one minute so we can compare speeds easily.

Meter per Hour (m/h)

Meter per hour is a very slow speed unit that tells how many meters something moves in one hour.

Sidereal Minute

A sidereal minute is a time unit used in astronomy, based on Earth spinning once relative to the stars, and is slightly shorter than a normal minute.

Synodic Month

A synodic month is the time the Moon takes to go from one full moon to the next, and it is about 29 and a half days long.

Microsecond

A microsecond is a very short unit of time that helps scientists and computer engineers measure fast events and signals with high accuracy.

Millennium

A millennium is a time unit equal to one thousand years, used to talk about history, calendars, and very long periods of time in a clear simple way.

Millisecond

A millisecond is a unit of time equal to one thousandth of a second, useful for measuring very quick events in science, technology, games, and daily life.

Muon mass

Muon mass is the standard size of matter for the muon particle, helping scientists describe its weight, energy and behavior in modern physics experiments and space studies.

mina (Biblical Hebrew)

The mina in Biblical Hebrew is an old unit of weight and money that helps us understand trade, value and measurements in Bible times.

microgram

A microgram is a very small unit of mass used to measure tiny amounts of substances in medicine, science, and nutrition.

megagram

A megagram is a large metric unit for measuring mass, equal to one million grams or one thousand kilograms, useful for very heavy objects.

Minim (Uk)

The minim UK is a very small old British unit for liquid medicine that helps you read and convert historic recipes into modern milliliters.

Minim (Us)

A minim (US) is a very tiny old medicine volume unit that is about one drop of liquid and is now mostly replaced by milliliters.

Microliter

Learn what a microliter is, how tiny it is, how to change it to other units, and where this small volume unit is used in science and medicine.

Megaliter

Learn what a megaliter is, how large it is, where it is used, and how to change it into other volume units in simple steps.

Mile (US Survey)

The mile (US survey) is a special mile used in American land maps and property lines, slightly longer than the regular mile you see on road signs.

Megameter

A megameter is a very large metric length unit used to measure huge distances such as across countries or parts of planets.

Mebibyte (MiB)

A mebibyte is a unit for measuring digital data size, based on powers of two, and it is mainly used for computer memory and some software tools.

Megabyte (MB)

A megabyte MB is a unit used to measure digital information, usually file size or storage space, and helps you understand how large a file or folder is.

Megabit (Mbit)

A megabit Mbit is a unit for measuring digital data, mostly used for internet speed, equal to one million bits and helps compare how fast data moves online.

Millibar (mbar)

A millibar is a small unit used to measure air pressure, often seen in weather reports to show if the air is high or low pressure.

Mach (Ma)

Mach, written as Ma, is a way to compare a speed to the speed of sound, so it tells you how many times faster or slower something moves than sound.

Miles per Hour (mph)

Miles per hour is a unit that tells you how many miles you travel in one hour, used to measure speed for cars, trains, and other moving things.

Meters per Second (m/s)

Meters per second m/s is a speed unit that shows how many meters something moves in one second, useful in science and everyday life.

Month

A month is a unit of time that is used to divide a year into smaller parts for calendars and everyday life.

Minute

A minute is a unit of time that equals 60 seconds and helps us measure short everyday events like brushing teeth, waiting for a bus, or timing a game.

Milligram

A milligram is a very small unit of mass used to measure tiny amounts of things like medicine, vitamins, and chemicals.

Milliliter (mL)

A milliliter is a small unit for measuring liquid volume, useful in cooking, science, and medicine to show how much space a liquid fills.

Marla (marla)

Marla is a traditional unit of land area used in South Asia that helps people measure and compare the size of plots and fields.

Micrometer

A micrometer is a very small unit of length used to measure things like cells, hair, and tiny machine parts.

Millimeter

A millimeter is a very small unit of length used to measure tiny distances accurately in science, school, and everyday life.

Mile

A mile is a unit used to measure long distances on land, like how far cities are from each other or how long a road or race is.

Meter

A meter is a basic unit for measuring length or distance in the metric system.

N

Nibble

A nibble is a small unit in computers equal to 4 bits, which is half of a byte, and it is often used with binary and hexadecimal numbers.

Newton-meter (N·m)

A newton meter is a unit that measures how much turning force or work is used when something is pushed or pulled over a distance.

Newton per Square Millimeter (N/mm²)

Newton per square millimeter is a metric unit that measures how much force presses on a very small area of material.

Newton per Square Centimeter (N/cm²)

Newton per square centimeter is a unit that tells how much push or pull is applied on each tiny square of area and helps compare different pressure values easily.

Newton per Square Meter (N/m²)

Newton per square meter is a metric unit that measures how much force presses on each square meter of area, helping compare pressure in science, weather, and engineering.

Novennial

Novennial means something that lasts nine years or happens every nine years, and it helps you talk clearly about long time periods and repeated events.

Nanosecond

A nanosecond is a very tiny unit of time that helps us measure extremely fast events in science, computers, and electronics.

Neutron mass

Learn what neutron mass is, its exact value, how it compares to other particles, and how to convert it into kilograms, atomic mass units, and energy units.

nanogram

A nanogram is a very tiny unit of mass that helps scientists measure extremely small amounts of substances like chemicals, medicines, and pollution.

Nanoliter

A nanoliter is a very tiny amount of liquid, helpful for science and medicine when only a millionth of a drop is needed.

Nautical mile

A nautical mile is a special way to measure distance at sea and in the air, linked to Earths shape and used by ships and planes worldwide.

Nanometer

A nanometer is a very small length unit used to measure atoms light and tiny devices, helping scientists and engineers understand and build things at the smallest scales.

O

Octet

An octet is a unit of computer data that always equals 8 bits, which helps avoid confusion when talking about digital information sizes.

Octennial

Octennial is a time word that means something happens every eight years or lasts for eight years.

Ounce

An ounce is a small unit for measuring weight that is often used for food, precious metals and mail, and it helps compare light objects quickly and easily.

P

Pound-force inch (lbf·in)

Learn what a pound force inch is, how it measures twisting force, and how to easily convert it to other torque units like newton meter and pound foot.

Pound-force foot (lbf·ft)

Pound-force foot is a unit that measures turning force, and it helps explain how strongly something like a bolt or a wheel is twisted.

Planck Time

Planck time is a tiny unit of time that shows the shortest meaningful moment in physics, used to study the universe at its very beginning.

Picosecond

A picosecond is a very tiny unit of time that equals one trillionth of a second and is used to measure extremely fast events like laser pulses and electronics.

Proton mass

Proton mass is the amount of matter in a single proton, which helps scientists measure atoms, compare particles and understand how the universe is built.

Planck mass

Planck mass is a special tiny mass built from nature constant numbers that helps scientists study gravity and quantum physics together.

pennyweight

A pennyweight is a small unit for weighing precious metals that helps jewelers and buyers measure gold and silver in a clear and trusted way.

poundal

A poundal is an old unit for measuring force that shows how hard something pushes or pulls in the foot pound second system.

pound-force square second/foot

Pound-force square second per foot is a way to measure mass in the English engineering system and is equal to the mass unit called a slug.

picogram

A picogram is a unit for very tiny masses, equal to one trillionth of a gram, used in science to measure things like DNA, hormones, and nanoparticles.

petagram

A petagram is a very large metric unit for mass, used for measuring huge amounts like global carbon or ice, equal to one quadrillion grams.

Pint (Uk)

Learn what a Pint (Uk) is, how big it is, and how to convert it to cups, liters and other units for cooking and drinks.

Picoliter

A picoliter is a very tiny unit for measuring liquid volume that helps scientists measure and compare extremely small drops of fluids very accurately.

Petaliter

A petaliter is a very large unit for measuring liquid volume, equal to one quadrillion liters, used mainly in science to describe huge amounts of water or other fluids.

Plaza

A plaza is a large open public space in a town or city where people meet, walk, shop, and join events, often surrounded by buildings, trees, and streets.

Point

A point is a very small unit of length used to measure font size, line thickness, and spacing in printing and digital design.

Pica

Pica is a printing and design unit used to measure text size and page layout, helping designers keep columns, margins and spacing neat and even.

Palm

A palm is an old unit of length based on the width of a human hand, useful for understanding ancient measures and simple size comparisons.

Petameter

A petameter is a very large unit for measuring length that equals one quadrillion meters and is mainly used for talking about huge distances in space.

Picometer

A picometer is a very tiny unit of length that helps scientists measure the size of atoms and other extremely small parts of matter.

Parsec

A parsec is a very large distance used in space science to measure how far away stars and galaxies are from us.

Pebibyte (PiB)

A pebibyte PiB is a very large unit of digital data, used in computers to measure big storage like servers and data centers with clear and exact size.

Petabyte (PB)

A petabyte is a very large unit for measuring digital data, used to describe huge collections of files, like those stored by big websites and data centers.

Pounds per Square Inch (psi)

Pounds per square inch, or psi, is a unit that tells you how much force presses on each tiny square of area on a surface.

Pascal (Pa)

The pascal is a metric unit for measuring pressure, helpful for understanding weather, engineering, tires and many science experiments in a clear and exact way.

Pressure

Pressure tells us how much force is pushing on a certain area, it helps us understand things like air, water, weather and even blood in our bodies.

US Pint (pt)

A US pint is a common unit for measuring liquid volume in the United States, useful for cooking, drinks, and understanding recipe sizes.

Q

Quinquennial

A quinquennial is a time unit that means a period of five years, used to measure events or plans that repeat every five years.

Quindecennial

A quindecennial is a time period of 15 years, used to describe events or plans that happen every 15 years.

quarter (UK)

The quarter is an old British unit used for weight and grain volume. Learn its simple meaning, symbols and how to convert it to modern units.

quarter (US)

The quarter (US) is an old weight unit equal to 25 pounds, useful for understanding historic farm records, trade documents, and converting between old and modern measurements.

quintal (metric)

A metric quintal is a unit of mass equal to 100 kilograms, often used to measure crops, goods and other heavy loads in simple round numbers.

US Quart (qt)

Learn what a US quart is, how it relates to cups and liters, and use simple conversions for cooking, shopping, and everyday measuring.

R

Rood

A rood is an old unit for measuring land area that equals a quarter of an acre and helps compare fields in simple size terms.

Reaumur [°r]

Reaumur is an old temperature scale that uses degrees Reaumur to show how hot or cold something is, mostly known today from history and special science uses.

Rankine [°R]

Learn what the Rankine degree is, how it measures temperature from absolute zero, and how to convert it to Celsius, Fahrenheit, and Kelvin.

Roman foot

Learn what the Roman foot is, how long it was, and how to convert it to modern units like centimeters, meters, and inches.

Roman mile

A Roman mile is an old Roman way to measure distance, based on 1000 steps by a soldier, and is a little shorter than the mile used today.

Rod

A rod is an old length unit used in land and map measurements, and this guide explains its meaning, history, symbols, and easy conversions.

S

Septennial

Septennial means something that happens every seven years or lasts seven years, and this glossary explains its meaning, history, use, and related time words.

Sidereal Second

A sidereal second is a time unit based on Earth turning once relative to the stars, and it is slightly shorter than the normal second used in everyday life.

Shake

A shake is a very tiny unit of time that scientists use to measure super fast events inside atoms.

Sun’s mass

Sun’s mass is a special unit used by astronomers to tell how heavy stars and other space objects are compared with our Sun.

shekel (Biblical Hebrew)

The Biblical Hebrew shekel was an old unit of weight and money, mainly made of silver, that people used in the Bible lands to measure value.

scruple (apothecary)

A scruple in apothecary weight is an old pharmacy unit of mass, equal to 20 grains or about 1.3 grams, once used to measure medicines.

stone (UK)

The stone UK is a traditional unit for measuring weight, mostly used in the United Kingdom and Ireland to tell how heavy a person, animal, or object is.

stone (US)

Learn what the stone US unit means, how it relates to pounds and kilograms, and how to quickly convert this older body weight unit in everyday life.

slug

Learn what the slug unit of mass is, how it compares to kilograms and pounds, and why some engineers still use it today.

Stere

Learn what a stere is, how this metric volume unit measures stacked firewood, and how to convert it to cubic meters, liters, and more.

Sabin

Learn what a sabin is, how it measures sound absorption, and why it matters in classrooms, theaters, and other rooms where echoes must be controlled.

Square Mil

A square mil is a very small unit used to measure area, often for thin wires and tiny parts in engineering work.

Square Pole

A square pole is an old land area unit that helps measure the size of fields and gardens, equal to one small part of an acre.

Square Perch

A square perch is an old land area unit used in farming and surveying that shows how much ground a piece of land covers.

Square Rod (US Survey)

A square rod US survey is an old land area unit that helps measure and compare the size of fields and property, especially in United States land records.

Square Rod

A square rod is an old unit for measuring land area, equal to 272.25 square feet, often found in old maps and property papers.

Square Chain

A square chain is an old land area unit based on the surveyor’s chain, often used in farms and maps, equal to one tenth of an acre.

Section (military unit)

A section in the military is a small group of soldiers who train and fight together as part of a bigger unit.

Square Foot (US Survey)

A square foot US survey is a unit for measuring land area in the United States based on the older US survey foot.

Square Mile (US Survey)

A square mile US survey is a special American area unit used in land maps and property records, very close in size to the regular square mile but not exactly the same.

Square Decimeter

A square decimeter is a metric unit for measuring area, useful for surfaces smaller than a square meter but larger than a square centimeter.

Square Dekameter

A square dekameter is a metric unit for measuring area that is useful for describing land size, fields, and medium sized spaces.

Square Hectometer

A square hectometer is a metric unit used to measure large areas of land, equal to one hectare or ten thousand square meters.

Shaku

Shaku is a traditional Japanese length unit that is a bit longer than 30 centimeters and is still used in some building plans and crafts.

Stade

The stade is an old Greek length unit used for race tracks and maps, usually about 185 meters long.

Span

A span is an old body based length unit, about the width of a stretched hand, useful for understanding history and converting to modern units like centimeters and inches.

Standard Atmosphere (atm)

The standard atmosphere or atm is a unit that measures how strong air pushes on things, called pressure, and it is based on average air pressure at sea level.

Speed

Speed is how fast something moves in a certain time and helps us measure and compare motion in daily life and science.

Second

A second is the basic unit of time that measures very short moments in clocks, science and daily life all around the world.

Square Inch (in²)

A square inch is a small unit for measuring area, meaning the space inside a shape that is one inch long and one inch wide.

Square Feet (ft²)

Square feet is a unit for measuring area, often used to describe the size of rooms, houses, and land, especially in the United States and other English speaking countries.

Square Yard (yd²)

A square yard is an area unit used to measure surfaces like floors or land, especially in the US and UK, equal to a square 1 yard on each side.

Square Mile (mi²)

A square mile is a unit used to measure large areas of land and helps compare the size of cities, countries and other big places in a simple way.

Square Nanometer (nm²)

A square nanometer is a very tiny unit for measuring area, used in science to describe the size of atoms, molecules, and parts of modern technology.

Square Micrometer (µm²)

A square micrometer is a very tiny unit of area used to measure very small surfaces like parts of cells, microchips, and other microscopic objects.

Square Millimeter (mm²)

A square millimeter is a very small unit for measuring area, equal to a square 1 millimeter long on each side, useful for tiny objects and details.

Square Centimeter (cm²)

A square centimeter is a small unit for measuring area, useful for describing the size of flat things like paper, screens, labels, and small surfaces.

Square Kilometer (km²)

A square kilometer is a way to measure large areas of land, like cities or forests, and helps compare sizes in a clear and simple way.

Square Meter (m²)

A square meter is a unit for measuring area, used worldwide to describe the size of rooms, land, and objects in the metric system.

T

Ton of TNT

Ton of TNT is an energy unit that shows how powerful an explosion is by comparing it to the energy in one ton of TNT explosive.

Therm

A therm is a unit of heat energy often used on gas bills to show how much natural gas you used.

Technical Atmosphere (at)

Learn what the technical atmosphere at is, how it measures pressure, how it compares to pascal and bar, and how to convert it for science and engineering.

talent (Biblical Hebrew)

A Biblical Hebrew talent is an old Bible weight unit that measured a very heavy load, used to weigh metals like silver and gold in ancient times.

tonne

A tonne is a metric unit for measuring mass that equals 1,000 kilograms, used worldwide in science, trade, and everyday life.

teragram

A teragram is a very large unit of mass used by scientists to measure huge amounts like pollution or carbon in the air.

ton (long)

A long ton is a weight unit used in the United Kingdom that is a little bigger than a metric ton and the short ton used in the United States.

ton (short)

A short ton is a unit of weight used mainly in the United States and equals 2,000 pounds or about 907 kilograms.

Tun

A tun is a very large old style barrel used as a unit to measure big amounts of liquid like wine or beer.

Ton Register

A ton register is a ship volume unit that counts 100 cubic feet of inside space to help measure how big ships are for rules, fees and cargo planning.

Teaspoon (Uk)

A Teaspoon (UK) is a small volume unit used in British recipes, equal to exactly 5 milliliters, helpful for measuring small amounts of liquids and dry ingredients.

Teaspoon (Metric)

A metric teaspoon is a small measure for liquid or dry ingredients, fixed at 5 milliliters, used in recipes and medicine so amounts are clear and easy to follow.

Tablespoon (Uk)

A UK tablespoon is a kitchen unit for volume, mainly used in recipes, and it helps measure small amounts of liquids or powders quickly and clearly.

Tablespoon (Metric)

A metric tablespoon is a cooking measure equal to 15 milliliters, used in many recipes to measure liquids and small amounts of dry ingredients accurately.

Teraliter

A teraliter is a very large metric unit for measuring liquid volume, useful for talking about oceans, lakes and water supplies in an easy to compare way.

Triple point of water

The triple point of water is a special temperature and pressure where ice, liquid water and water vapor can all exist together in perfect balance.

Toise

A toise is an old French unit of length, about two meters long, once used for building, maps, and land measuring before the metric system.

Terameter

A terameter is a very large distance unit that equals one trillion meters and helps measure huge spaces in astronomy and space science.

Tebibyte (TiB)

A tebibyte TiB is a unit for measuring digital data that uses binary counting and helps show the true size of computer storage.

Terabyte (TB)

A terabyte is a big unit for measuring digital data size that helps you understand how much information can be stored on devices like phones, laptops, or hard drives.

Terabit (Tbit)

A terabit Tbit is a very large unit for counting digital bits and is often used to show internet and network speed.

Torr (torr)

Torr is a unit to measure pressure, often used in vacuum science, defined as exactly 1 divided by 760 of standard atmosphere, useful for comparing very low pressures.

Time

Time is a way to measure how long things last and the order in which events happen so we can plan, compare and organize our lives.

Ton

A ton is a large unit of weight used in trade and science, but its exact size changes by country, so it is important to know which type of ton you mean.

Teaspoon US (tsp)

Learn what the US teaspoon is, how big it is in milliliters, and how to use it for easy and correct measurements in cooking and baking.

Tablespoon US (tbsp)

A Tablespoon US tbsp is a cooking volume unit that helps you measure small amounts of liquids and dry ingredients quickly and the same way every time.

Temperature

Temperature tells us how hot or cold something is, and this guide explains its meaning, symbols, units, and simple conversions in clear words.

U

US Ounce (fl oz)

The US fluid ounce fl oz is a small unit for measuring liquid volume, useful for cooking, drinks, and quick conversions to cups or milliliters.

V

Varas Conuqueras Cuad

Varas Conuqueras Cuad is an old area unit based on the Spanish vara, once used to measure fields and farm land.

Varas Castellanas Cuad

Varas Castellanas Cuad is an old Spanish area unit used to measure land, now mostly converted into square meters for easier use today.

Verst

A verst is an old Russian unit of distance, about one kilometer long, useful for understanding historical maps, books, and travel records from Russia and Eastern Europe.

Vara

A vara is an old Spanish unit of length that helps us understand historical land records, maps, and measurements in Spain, Portugal, Texas and many parts of Latin America.

Volume

Volume is the amount of space that a solid, liquid, or gas takes up, and we use it to measure how big or full something is.

W

Watt-second (Ws)

A watt second is a small unit of energy that shows how much work is done when one watt of power is used for one second.

Watt-hour (Wh)

A watt hour is a simple way to measure how much electrical energy is used or stored over time so you can compare devices and read energy bills easily.

Week

A week is a common time unit that equals seven days and helps people plan work, school, travel and daily life in an easy, repeating pattern.

Weight

Weight is how heavy something is, based on how strongly gravity pulls on it, and we measure it with units so we can compare and trade fairly.

X

Z

Zhang

Zhang is a traditional Chinese length unit, about 3.3 meters, that helps us understand old building plans, maps, and stories from China.