Usually said to someone when it appears that they have a boner.

Said to embarass/draw attention to said person

Banana can be replaced with a multitude of things, i.e cucumber, pencil, roll of quarters, mint container, etc.
Guy 1: *walks into room*
Guy 2: Hey is that a banana in your pocket or are you just happy to see me?
Guy 1: *looks down*
Everyone: *Laughs*
by Neon Ninja Kills You November 1, 2009
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