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1.
ripp·le·bum rip-all-bum(n.)

1. A bum which has, engraved upon it, a ripple pattern, often a result of sitting upon textured or ridged surfaces for an extensive period of time.

2. A bum which has a pattern upon it, akin to the side of a potato chip, like a ripple.
F: I sat on that bleacher for so long I got ripple-bum!
K: Holy crap!

or

K: hahaha!! what better way to start my day than seeing your rippled-potato-chip bums in my head lol xD i hope they've plumped right back up now hahah :D

F: LoL! bums!
by Flank June 20, 2008