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1.
The action of jabbing your thumbnail into another's arm. Depending on boniness of the finger and fingernail length, the doom finger can be VERY painful! Especially when done repeatedly. The user makes a fist with the thumb sticking out over the index, much like a knuckle sandwich but the thumb instead.
Jessica: *holds up doom finger*

Abby: *sees it and cowers*
by Hazard89 March 30, 2011