Douglas Harper's Etymology Dictionary
Wiktionary
clusterfuck
n. (context slang vulgar English) A chaotic situation where everything seems to go wrong. It is often caused by incompetence, communication failure, or a complex environment. vb. (context vulgar English) To fuck up, to make a total mess of.
Usage examples of "clusterfuck".
And then he could elude the Sigs and follow the woman who had turned all their careful plans and procedures into a complete clusterfuck.
Adams had been in some nasty clusterfucks in his time and walked out of every one.
This is going to turn into the mother of all clusterfucks, and it's going to do it fast.
Mother of all clusterfucks wasn't an observation his SAC or SSA would appreciate.