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

Here's a look at the trends just this week, with the average price per gallon data that is updated daily by AAA-The Auto Club Group. — Paula Wethington, CBS News, 16 Sep. 2026

Per-gallon prices for diesel, the fuel type utilized in trucks and trains, hit fresh records on Wednesday. — Jeff Cox,darla Mercado, Cfp®, CNBC, 16 Sep. 2026

Reno and its community water provider broke ground on a water purification plant that will treat roughly 2 million gallons of wastewater a day, bring it to drinking-water standards and send it into a groundwater aquifer, a first for Nevada. — Piper Heath, Los Angeles Times, 16 Sep. 2026

The result may appear in parts per million (ppm), milligrams per liter (mg/L) or grains per gallon (gpg). — Ryan Brennan, Kansas City Star, 15 Sep. 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