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

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

From MarketWatch • Mar. 31, 2026

Measured levels ranged from nanograms per liter in water to micrograms per kilogram in sediment.

From Science Daily • Mar. 21, 2026

Environmental Protection Agency’s aquatic life safety threshold of 8.1 micrograms per liter.

From Los Angeles Times • Mar. 20, 2026

If subsidized RON95 fuel prices are raised after the government’s current two-month freeze ends, every 0.10 ringgit per liter increase could add about 0.1 percentage point to inflation, they note.

From The Wall Street Journal • Mar. 12, 2026

So each liter of hydrazine has enough hydrogen for two liters of water.

From "The Martian" by Andy Weir