n. A pocket in the back of a pair of leggings used to store items such as keys, money, or a cell phone while excersizing. Often used as a comparison for something that is to small or unuseful.
"Where am I supposed to keep my water bottle while I'm hiking?" "Keep it on your shoes..." " That is almost as unuseful as a ButtPocket!"
by HJG123 January 06, 2017