verb.
"Givin someone a thumb-kin"

Sticking your thumb real hard and fast into someones anus.
"I'm gonna give you a fucking thumb-kin, dude"
"Look man, you want me to do a thumb-kin"
"Yo niggaz bettah watch out cuz when i do ma thumb-kin"
by Simon Talek September 10, 2006
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noun

Something that giving a thumbs up to is greatly ironic.
The definitions of "thumb-kin" are thumb-kins.
by Palec Smuk January 26, 2007
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noun

Something that giving a thumbs up to is greatly ironic.
The definitions of "thumb-kin" are thumb-kins.
by Palec Smuk January 21, 2007
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