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

Firefighters used 18 million gallons of water to put it out, a process that took days. —Ashley Portillo, CBS News, 8 Jan. 2026

The cider maker produced 89,907 gallons, or 2,900 barrels, in 2024, up a little more than 4% from the year earlier, according to the most recent numbers provided by the Alcoholic Beverage Control Division of the Arkansas Department of Finance and Administration. —Arkansas Online, 7 Jan. 2026

The estimated volume of wastewater contaminating the San Gabriel River is more than 100,000 gallons, per the release. —Rachel Raposas, PEOPLE, 7 Jan. 2026

This week, operators at Oroville Dam, the tallest dam in the United States, which holds back California’s second-largest reservoir, opened the spillway gates and began releasing billions of gallons of water down the massive concrete spillway into the Feather River below. —Paul Rogers, Mercury News, 7 Jan. 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