1. (noun) a lesbian with a dildo strapped to her forehead
2. (verb) to penetrate another with a dildo strapped to ones forehead, like a crazed unicorn.
3. (verb) to battle a rival lesbian to near death by clashing forehead dildos in a stag-like manner.
1. The screwnicorn winced as her dildo hit the doorframe.
2. The whiplash injury was a result of a drunken screwnicorn.
3. The angry girls had a screwnicorn over the hot chick.