A thot who sucks a lot of dick. This term is used in Queens, NYC, and Long Island. Up and coming slang word to call out thots in public lowkey or directly say it to a dumb girl for a laugh with the boys.
When thehairline of a person is so low that their forehead becomes reclassified a "threehead". This also suggests that their forehead is only about three finger widths high.
its cold outside. youre not wearing a jacket. you see michelle and randy huddeled close together for warmth. tempted to join? dont be afraid. call "threesie" and you're in :)