1) A bumbling, stupid, inept person.
2) A confusing mess; a conundrum; any chaotic situation
3) A person of low intelligence who gets himself into a comical quandary.
> "Frank just took off for the store and forgot his wallet again. What a chucklefuck!"
> "When the storm hit in the middle of the parade, the whole festival became one big chucklefuck."
> "That chucklefuck Frank got drunk and drank from that shampoo bottle."