It would be compose of two words: "cuss" and "out"
According to Urban Dictionary:
1. cuss out
To cuss somebody/something.
"I dont like to cuss out people, but sometimes it is necessary."
2. cuss out
when somebody screams a long string of cuss words at another in the hopes of insulting them. This is a tactic used by dolts lacking the vocabulary to actually belt out a witty insult.