English Reference

Word

gallon

Phoneticsgal·lon

US/ˈɡæɫən/

UK/ɡˈælən/

Definitions

01unit of volume

B1

n. a unit for measuring liquids. In the US, it is about 3.8 litres, and in the UK, it is about 4.5 litres.

n. a unit of liquid volume. The US liquid gallon is defined as 231 cubic inches, whereas the imperial gallon is defined as 4.54609 litres.

“The car's tank holds about twelve gallons of petrol.”

“With fuel prices rising, many commuters are calculating exactly how many miles they can get out of a single gallon of petrol.”

Usage

Often used when talking about fuel or milk.

02large amount

C1

n. a very large amount of a liquid.

n. a large quantity of liquid, used figuratively in the plural to emphasise volume.

“We drank gallons of water after our long hike in the sun.”

“The children managed to spill gallons of paint across the new carpet before anyone noticed what they were doing.”

Informal

Usage

Almost always used in the plural form 'gallons'.

Synonyms

Antonyms

Real-World Examples

“Based on its size and colour, Amos estimates that the spill is "well over" 100,000 US gallons (380,000 litres) of oil.”
BBC News · 14 Aug 2026
“Yet online images show Russian drivers sitting in cars for hours waiting to get a few gallons of fuel.”
The Conversation · 4 Aug 2026
“Idling in the United States uses more than 6 billion gallons of fuel at an estimated cost of more than US$20 billion to consumers and businesses each year.”
The Conversation · 31 Jul 2026

Etymology

From Middle English gallon, galoun, galun, from Old Northern French galun, galon (“liquid measure”) (compare Old French jalon), from Late Latin galum, galus (“measure of wine”), from Vulgar Latin galla (“vessel”), possibly from Gaulish galla, ultimately from Proto-Indo-European *kel- (“goblet”). Cognate with Ancient Greek κύλιξ (kúlix, “cup”), Sanskrit कलश (kalaśa, “jar, pitcher; measure of liquid”). Related to Old French gille (“wine measure”) (from Medieval Latin gillō (“earthenware jar”)), Old French jale (“bowl”), Old French jaloie (“measure of capacity”).

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

Related words

This entry

Level
C1 · Advanced
Frequency
Frequent
Updated

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