liter

American  

[lee-ter] / ˈli tər /

especially British, litre

noun

1. a unit of capacity redefined in 1964 by a reduction of 28 parts in a million to be exactly equal to one cubic decimeter. It is equivalent to 1.0567 U.S. liquid quarts and is equal to the volume of one kilogram of distilled water at 4°C. l

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liter British  

/ ˈliːtə /

noun

1. the US spelling of litre

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liter Scientific  

/ lē′tər /

1. The basic unit of liquid volume or capacity in the metric system, equal to 1.06 quart or 2.12 pints.

2. See Table at measurement

3. The basic unit of dry volume or capacity in the metric system, equal to 0.90 quart or 1.82 pint.

4. See Table at measurement

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Etymology

Origin of liter

1800–10; < French litre, back formation from litron an old measure of capacity, derivative (with -on noun suffix) of Medieval Latin litra < Greek lítra pound

Compare meaning

How does liter compare to similar and commonly confused words? Explore the most common comparisons:

• gallon vs. liter
• liter vs. milliliter
• pint vs. liter

Explanation

A liter is a liquid unit of measurement. Drinking a liter of water everyday is good for you, though drinking a liter of diet soda probably isn't. A liter is a metric unit that measures volume. You can also spell the word litre, which is actually the most common spelling outside of the United States. Liters most often measure liquids — a large bottle of Coke or Pepsi, for example, typically comes in a two liter size. The French word litre comes from the obsolete litron, which once measured amounts of grain, with its Greek root litra, or "pound."

Example Sentences

Doctors said she lost a liter of blood and her complications were likely worse for having been forced to wait so long to deliver.

From Salon • May 27, 2026

One system, a 100 liter bioreactor nicknamed "Shrek," is currently used to process industrial flue gas as part of efforts to reduce air pollution.

From Science Daily • May 12, 2026

By mid to late April, standard diesel in Manila cost 123 pesos per liter, or about $7.69 a gallon, according to one reading from the Philippines Energy Department.

From The Wall Street Journal • Apr. 28, 2026

Each liter costs a little less than $3,000, according to Interlune.

From MarketWatch • Mar. 31, 2026

Also, I'll lose half a liter of water per day to breathing until the humidity in the Hab reaches its maximum and water starts condensing on every surface.

From "The Martian" by Andy Weir