Half Aborted is the look you get when the coat hanger pokes all the wrong places and you end up with an unwanted baby with a fucked up face. Or the result of a baby from a botched abortion that looks unwanted.
It can also refer to people who are just ugly or weird looking because of underdeveloped or disproportionate features.
He was half-aborted looking
A no good bottom of the barrel type person
Hey have you meet Kenny vessey? Yeah that dudes a slimy half aborted fetus!