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1.
Aack Pronunciation Key - Show Spelled Pronunciationaak

1. when you can't tell when a person's back stops and their ass begins.
2. the rear part of the human body, extending from the lower end of the ass to the upper back.
3. Otherwise known as Jaack (Jay's Aack). Not to be confused with Jack (JD), Jay's drink of choice.
Jay you should really shave your Aack.
Kara, Jay's showing his Aack again.
Jay, Get your Aack off the ice.
by BIG5HOLE October 25, 2006