1 definition by nophone

Noun: The Thumb.

Specifically when you attempt to insert your thumb into a girl's asshole prior to having anal sex with her in an attempt to gauge how well received your cock will be.
Nate: I tried to fuck my girlfriend in the ass and she almost killed me.

Steve: n00bish mistake dude! Next time send the ambassador in first

Nate: Like a little representative for my cock?

Steve: Exactly

Paul & Derek: LOL ROFL ROFL ROFL
by nophone February 14, 2009
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