1 definition by KillahKoba™

The situation arises when a male uses the washroom, and when exposing himself to urinate, contacts his balls with his thumb. This results in a recognizable nutsack-like odor on your thumb. Preventable by handwashing and using the lil hole in the front of your boxers.
I was on a date with Steve last night, and everything was fine until halfway through dinner; he came back from the washroom and all I could smell was his ballthumb
by KillahKoba™ July 4, 2010
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