(US) One-eighth of a U.S. bushel or approximately 4.405 liters for dry goods (a "U.S. dry gallon").
(in the plural, informal) A large quantity (of any liquid).
The pipe burst and gallons of water flooded into the kitchen.
Origin of gallon
Middle English a liquid measurefrom Old North French galon
American Heritage Dictionary of the English Language, 5th Edition
From Anglo-Norman, Old Northern French galon, ultimately from Medieval Latin galleta. Cf. also French jalon.
Gallon Sentence Examples
How much does a gallon of milk weigh?
He assumes that in what is considered a good producing district the amount of petroleum which can be obtained from a cubic foot of rock would not be more than a gallon, and that the average thickness of the oil-bearing rock would not exceed 5 ft.
Each gallon of their waters contains about 28.5 cub.