Jerry Look up Jerry at Dictionary.com
World War I British Army slang for "German," 1919, probably an alteration of German, but also said to be from the shape of the Ger. helmet, which was like a jerry, British slang for "chamber pot" (1827), probably an abbreviation of jeroboam. Hence jerry-can "5-gallon metal container" (1943), a type first used by German troops in World War II, later adopted by the Allies.