To act in a stupid, futile, or otherwise misguided fashion.
He had a chance of hooking up with the gal until he mooked it up by spilling his drink on her dress.
by Mugsy August 14, 2003
Noun: one who acts stupid, dumb, slow, lazy, or clumsy.
You dumb mook, you stepped on my pizza!
by Steve Smith October 18, 2004