A bra or bra additives that cause a girl's breasts to appear a size or two larger than they actually are.

Also a much cheaper and less permanent version of fake titties.
guy 1:Yeah, her tits looked great, until I got her naked and saw she was just wearing rent-a-boobies!

guy 2: Snap! false advertising!

guy 1: plus her bra weighed about five pounds from all the padding!
by lingling4canada February 9, 2010
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