Someone you keep around just in case your current relationship with your boyfriend/girlfriend falls apart. Thus saving you the work and search of your partner for your"rebound relationship".
Guy 1: Who's that ugly chick I always see you with when your not with your girlfriend?
Guy2: That's Tracy, shes just a bottom keeper, you know kinda like a "bottom feeder".
Guy1: Ha Ha.
by FAWKGIRL January 10, 2014
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