gallon

noun

gal·​lon ˈga-lən How to pronounce gallon (audio)
: 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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
An acre-foot is roughly 326,000 gallons, enough to supply two typical households for a year. — Swasti Singhai, USA Today, 4 Aug. 2026 In the back, gallon-size gourds used by Rwandans for fermenting and brewing—some hollowed out more than 80 years ago—were displayed as prized heirlooms. — Alicia Erickson, Travel + Leisure, 4 Aug. 2026 By comparison, Texas data centers directly used 8 billion gallons of water for cooling purposes, but many such data centers rely on water-intensive power generation sources. — Jeremy Hsu, ArsTechnica, 4 Aug. 2026 But interest rates are high, a gallon of gasoline costs more because of the Iran war, tariffs are still reshaping the economy and by the White House’s own estimates there is a national shortage of housing. — Darlene Superville, Fortune, 4 Aug. 2026 See All Example Sentences for gallon

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

Time Traveler
The first known use of gallon was in the 13th century

Phrases Containing gallon

Rhymes for gallon

See All Rhymes for gallon

Browse Nearby Words

Gallomania
gallon
gallonage
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Cite this Entry

“Gallon.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/gallon. Accessed 5 Aug. 2026.

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Kids Definition

gallon

noun
gal·​lon ˈgal-ən How to pronounce gallon (audio)
: a unit of liquid capacity equal to 231 cubic inches or four quarts see measure

Medical Definition

gallon

noun
gal·​lon ˈgal-ən How to pronounce gallon (audio)
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

More from Merriam-Webster on gallon

Nglish: Translation of gallon for Spanish Speakers

Britannica.com: Encyclopedia article about gallon

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