gallon

noun

gal·​lon ˈga-lən 

: a unit of liquid capacity equal to 231 cubic inches or four quarts see Weights and Measures Table

Examples of gallon in a Sentence

Recent Examples on the Web

The National Park Service told USA TODAY the pool had leaked 16 million gallons a year. —Michelle Del Rey, USA Today, 17 June 2026

The diesel tax jumped slightly more than 9 cents per gallon in July 2022 after retail prices over the prior year had nearly doubled. —Keith M. Phaneuf, Hartford Courant, 16 June 2026

About 5 gallons of fuel leaked from the plane, but the scene was safely contained, authorities said. —Austin Turner, CBS News, 16 June 2026

The budget does not raise the state’s gas tax, but that tax is set to increase by 2 cents a gallon next month under laws that require adjustments tied to inflation rates. —Andrew Graham, Sacbee.com, 16 June 2026

Word History

Etymology

Middle English galun, galoun, galon, a liquid measure, borrowed from Anglo-French galun, galon, jalon, from Old French jal-, base of jaloie "container for liquids, bucket" (going back to Vulgar Latin *gallēta, of uncertain origin) + -on, diminutive or particularizing suffix, going back to Latin -ō, -ōn-, suffix of persons with a prominent feature

Note: Presumed *gallēta (attested as Medieval Latin galeta "wine vessel, liquid measure" in 11th-century texts) has been linked to several classical Greek words for containers, as kálathos "kind of basket, wine cooler," kēlástra "milk pail" (so glossed by Hesychius), though none of these fit formally; on the other hand, kēlḗtēs, kalḗtēs "sufferer from a hernia" (from kḗlē, kálē "tumor, hernia"; see -cele) fits formally but requires a contextual and semantic leap ("one swollen or ruptured" > "container"?).

First Known Use

13th century, in the meaning defined above

Phrases Containing gallon

• ten-gallon hat

Rhymes for gallon

• alan
• ballon
• talon
• concanavalin
• enkephalin
• trifluralin

Kids Definition

gallon

noun

gal·​lon ˈgal-ən 

: a unit of liquid capacity equal to 231 cubic inches or four quarts see measure

Medical Definition

gallon

noun

gal·​lon ˈgal-ən 

1

: a United States unit of liquid capacity equal to four quarts or 231 cubic inches or 3.785 liters

2

: a British unit of liquid and dry capacity equal to four quarts or 277.42 cubic inches or 4.544 liters

called also imperial gallon