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

This is particularly common in homes with 30- or 40-gallon water heaters that are drained quickly when multiple fixtures demand hot water at the same time, says Alex Atkinson, a plumber and HVAC technician at Super Brothers. —Kathy Barnes, Better Homes & Gardens, 9 Dec. 2025

Michigan gasoline prices continue to fall, with the state average per-gallon price down 33 cents from last month, AAA reports. —Keith Matheny, Freep.com, 8 Dec. 2025

Like the one from last January in which three and a half million gallons flooded the Mississippi River and all the ducks had to be rescued and cleaned. —Lizz Schumer, PEOPLE, 8 Dec. 2025

In 1969, a well located off Santa Barbara blew out, releasing millions of gallons of oil, which washed up onto beaches, killing wildlife and fouling the waterfront of the popular tourist destination. —John Ramos, CBS News, 8 Dec. 2025

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