Numpty is a Scottish way of saying stupid or dum something to call your teacher when you finish your work
An idiot.
Usually used by british people.
Lea: I think I'm in love with Joe.
Sarah: but he's Kristens boyfriend! and she's your bestfriend!
Lea: Yeah, I know but who cares?
Sarah: oh, you are such a numpty.
A person who has gone and made a fool of oneself; with excessive amount of drug use, specifically frying one’s brain and disengaging in all use of basic motor functions.
A numpty
Damn, He’s gone and fucked himself. What a numpty.