A large quantity (of any liquid).
one-eighth of a U.S. bushel or approximately 4.405 liters for dry goods (a "U.S. dry gallon").
231 cubic inches or approximately 3.785 liters for liquids (a "U.S. liquid gallon")
exactly 4.54609 liters; an imperial gallon
A unit of volume, equivalent to eight pints
A large barrel or cask of indefinite contents, especially one containing from 100 to 140 gallons.
An English measure of capacity for liquids, containing 63 wine gallons, or about 52+¹⁄₂ imperial gallons; a half pipe.