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Pronounced: "Yack Yumbo"

Ordering a burger from Jack in the Box (Fast Food Restaurant on the West Coast) that is not listed on their menu. It is basically a Jumbo Jack and a taco. The taco is inserted in the Jumbo Jack for an extremely flavorful crunch. It is favorite treat, that originated in Los Angeles County in 1992.
"I am really hungry and only have $2, its time for a Jack Jumbo!"
by O.M.A.R. November 06, 2006