When you slap a girl on the head with your cock.
She had a bruise on her forehead from when I Tomacocked her last night.
by Lord Maher13 February 19, 2011
1 more definition
A penis shaped like a tomahawk. it's like a "battle axe cock" but smaller.. and only one-sided. AND, it's hairless. its basically like a stick with a semi-pointed, but still generally rounded, end; attached with a piece of leather primarily used for bashing... but a cock.
by jchap1590 July 22, 2011