- gallon, gal - United States liquid unit equal to 4 quarts or 3.785 liters
--1 is a kind of United States liquid unit
--1 is a part of barrel, bbl
--1 has parts: quart - gallon, Imperial gallon, congius - a British imperial capacity measure (liquid or dry) equal to 4 quarts or 4.545 liters
--2 is a kind of British capacity unit, Imperial capacity unit
--2 is a part of bushel; barrel, bbl; firkin
--2 has parts: quart