gallon

[gal-uh n] /ˈgæl ən/

noun

a common unit of capacity in English-speaking countries, equal to four quarts, the U.S. standard gallon being equal to 231 cubic inches (3.7853 liters), and the British imperial gallon to 277.42 cubic inches (4.546 liters).

Abbreviation: gal.

Origin

1250-1300; Middle English galo(u)n, gallon < Old North French galon, derivative from base of Medieval Latin gallēta jug, bucket, of uncertain origin

Examples from the web for gallon

Dead leaves drift on the green, cloudy water that's nearly to the brim of the six-million-gallon open concrete reservoir.
He raced to the grocery store and bought half a gallon of chocolate ice cream.
Twenty or thirty gallons, boiled down, will yield a gallon of light amber syrup.
Red-eared sliders, for example were priced fairly cheap and often taken home on impulse with a twenty gallon tank in hand.
The bike uses eight gallon water bottles attached to a metal frame to keep it afloat.
Because butanol packs more energy per gallon than ethanol does, cars running on butanol get better mileage.
However the cost of hydrogen is still sky high cost quite a few times the energy equivalent of a gallon of gas.
Gasoline at about four dollars a gallon, slowly climbs higher,then back then higher again.
So the next time you reach into the dairy case, grab the quart or gallon-size yogurt instead of the single-serving cups.
Researchers have now uncovered the protein that holds the key for producing this fuel by the gallon.

British Dictionary definitions for gallon

gallon

/ˈɡælən/

noun

(Brit) Also called imperial gallon. a unit of capacity equal to 277.42 cubic inches. 1 Brit gallon is equivalent to 1.20 US gallons or 4.55 litres

(US) a unit of capacity equal to 231 cubic inches. 1 US gallon is equivalent to 0.83 imperial gallon or 3.79 litres

(pl) great quantities

Word Origin

C13: from Old Northern French galon (Old French jalon), perhaps of Celtic origin

Word Origin and History for gallon

liquid measure, late 13c., from Old North French galon, corresponding to Old French jalon "liquid measure," related to jale "bowl," from Medieval Latin diminutive form galleta "bucket, pail," also "a measure of wine," of unknown origin, perhaps from Gaulish galla "vessel."

gallon in Medicine

gallon gal·lon (gāl'ən)
n.
Abbr. gal.
A unit of volume in the U.S. Customary System, used in liquid measure, equal to 4 quarts, 231 cubic inches, or 8.3389 pounds of distilled water (3.7853 liters).

gallon in Science

gallon

(gāl'ən)
A unit of liquid volume or capacity in the US Customary System equal to 4 quarts (3.79 liters). See Table at measurement.