Other forms: gallons
A gallon is a large unit of liquid volume. A gallon of milk, miles per gallon, four gallons.
There are two of them and they differ by a fifth: the imperial gallon is about 4.55 litres and the American about 3.79, which makes fuel economy figures across the Atlantic incomparable without conversion. Britain now sells fuel in litres and still quotes miles per gallon.
1noungallonA large unit of liquid volume.
“We bought a gallon of milk and a loaf of bread at the corner shop.”
gallon is a unit of volume.
Old Northern French galun names a liquid measure, from a Latin word for a wine measure.
Proto-Indo-European
*kel- — goblet
cel-gau
*galla
Vulgar Latin
*galla — vessel
Latin
galum
fro-nor
galun
Middle English
gallon
English, today
gallon
Built from
From Middle English gallon, galoun, galun, from fro-nor galun, galon (“liquid measure”) (compare Old French jalon), from Latin galum, galus (“measure of wine”), from Vulgar Latin galla (“vessel”), possibly from cel-gau galla, ultimately from Proto-Indo-European kel- (“goblet”). Cognate with Ancient Greek κύλιξ (“cup”), Sanskrit कलश (“jar, pitcher; measure of liquid”). Related to Old French gille (“wine measure”) (from Medieval Latin gillō (“earthenware jar”)), Old French jale (“bowl”), Old French jaloie (“measure of capacity”).
Etymology from Wiktionary, CC BY-SA