gal·​lon | \ˈga-lən \

Definition of gallon 

: 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 Obama Administration nonetheless sought to compel auto makers to produce ever more electric cars by requiring an average fleet fuel economy of 54.5 miles per gallon by 2025. The Editorial Board, WSJ, "Government Motors Is Back," 11 Nov. 2018 Among refined products, gasoline futures for December delivery fell 0.2% to $1.6443 a gallon. Dan Molinski, WSJ, "U.S. Oil Enters Bear Market on Rising Inventories, Worries of Oversupply," 8 Nov. 2018 Opponents say that Initiative 1631 would increase gas prices by $0.14 per gallon, and utilities in southeastern Washington, where less hydropower is available, say their customers' electricity bills would increase as well. Megan Geuss, Ars Technica, "States will vote on these energy and environment issues in midterm elections," 4 Nov. 2018 Federal fuel-efficiency standards would be frozen in two years, barely cracking 40 miles per gallon. Alissa Walker, Curbed, "Mayors are fighting the EPA’s fuel-efficiency rollback. What cities need are fewer cars.," 2 Aug. 2018 At the same time, the draft says that people will drive less if their vehicles get fewer miles per gallon, lowering the risk of crashes. Tom Krisher And Ellen Knickmeyer, Fox News, "Lower fuel economy standards will save lives, Trump administration says," 1 Aug. 2018 Twenty-five years ago, gas cost $1.16 a gallon and Harvard tuition was $23,500 annually. Denise Coffey, Courant Community, "Ekonk Community Grange Gives 14 Service Awards," 15 May 2018 In June, the average U.S. retail price of a gallon of gasoline was $2.97, up more than 20% from the same time last year. Eric Newcomer,, "Why Silicon Valley doesn't mind rising gas prices," 6 July 2018 Ways of stretching more miles out of a gallon of fuel run from the practical, keep it under 65 mph, to the extravagant, buying premium gasoline, to the outright anti-Texan, buying a smaller vehicle. James Osborne, Houston Chronicle, "Where the rubber meets the road could kill your gas mileage," 3 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'gallon.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of gallon

13th century, in the meaning defined above

History and Etymology for gallon

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"?).

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Statistics for gallon

Last Updated

27 Nov 2018

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Time Traveler for gallon

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

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English Language Learners Definition of gallon

: a unit of liquid measurement equal to four U.S. quarts or 3.785 liters

: a unit of liquid measurement equal to four British quarts or 4.546 liters


gal·​lon | \ˈga-lən \

Kids Definition of gallon

: a unit of liquid capacity equal to four quarts (about 3.8 liters)


gal·​lon | \ˈgal-ən \

Medical Definition of gallon 

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

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More from Merriam-Webster on gallon

Rhyming Dictionary: Words that rhyme with gallon

Spanish Central: Translation of gallon

Nglish: Translation of gallon for Spanish Speakers

Britannica English: Translation of gallon for Arabic Speakers Encyclopedia article about gallon

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to make faulty or ineffective

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