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definitions

imperial gallon

noun
  1. a British gallon used in liquid and dry measurement equivalent to 1.2 U.S. gallons, or 4.54 liters.

Origin of imperial gallon

First recorded in 1830–40
Also called British gallon.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for imperial gallon

imperial gallon

noun
  1. a formal name for gallon (def. 1)
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012