gallon

American  

[gal-uhn] / ˈgæl ən /

noun

1. a common unit of capacity in English-speaking countries, equal to four quarts, the U.S. standard gallon being equal to 231 cubic inches (3.7853 liters), and the British imperial gallon to 277.42 cubic inches (4.546 liters). gal.

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gallon British  

/ ˈɡælən /

noun

1. Also called: imperial gallon.  a unit of capacity equal to 277.42 cubic inches. 1 Brit gallon is equivalent to 1.20 US gallons or 4.55 litres

2. a unit of capacity equal to 231 cubic inches. 1 US gallon is equivalent to 0.83 imperial gallon or 3.79 litres

3. (plural) great quantities

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gallon Scientific  

/ găl′ən /

1. A unit of liquid volume or capacity in the US Customary System equal to 4 quarts (3.79 liters).

2. See Table at measurement

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Etymology

Origin of gallon

First recorded in 1250–1300; Middle English galo(u)n, gallon, from Old North French galon, derivative from base of Medieval Latin gallēta “jug, bucket,” of uncertain origin

Compare meaning

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

• gallon vs. liter
• pint vs. gallon

Example Sentences

"That is a sizeable jump," he told AFP, pointing to a neon sign showing $3.27 for a gallon of regular gasoline.

From Barron's

The national average price of a gallon of regular unleaded gasoline rose to its highest price since the summer of 2024.

From The Wall Street Journal

Average U.S. diesel prices jumped 51 cents a gallon over the past week, according to GasBuddy, while gasoline costs climbed 32 cents.

From The Wall Street Journal

The average cost of a gallon of regular gas in California is around $4.91, up 26 cents from a week ago and 48 cents from a month ago, according to AAA.

From Los Angeles Times

Retail gasoline prices climbed to $3.25 per gallon in the U.S., up almost 27 cents compared with a week ago, according to AAA.

From MarketWatch