[noun] [C] - a unit for measuring volumeAn imperial gallon, used in Britain, is equal to 4546 cubic centimetres.A US gallon is equal to 3785 cubic centimetres.(informal) I love milk - I drink gallons (= a great amount) of the stuff.
GALLON
Meaning of GALLON in English
Cambridge English vocab. Кембриджский английский словарь. 2012