bust a nut - Wiktionary, the free dictionary
bust a nut (third-person singular simple present busts a nut, present participle busting a nut, simple past and past participle busted a nut or bust a nut)
- (idiomatic, slang, vulgar) To ejaculate.
It don't take long for me to bust a nut when I'm looking at a nice piece of ass.
- (idiomatic, slang, vulgar) To work very hard; to put in a lot of effort.
- (eject semen): bust, nut; see also Thesaurus:ejaculate
- (work very hard): bust one's balls, bust one's butt