A shortened form of nothing. But adopted, at least in central australia, to also mean no one. Also replaces no as a prefix as in "Nuth-one" for no-one. Note: Everynuth is a way of expressing nuth/no very strongly.. as in do u like soulja boy? EveryNUTH!
Hey man did u buy any smokes? Nuth
Did anyone come over last night? Nuth
Who are u with? Nuth-one
Short-hand for the word floccinaucinihilipilification, meaning the estimation of something as valueless (encountered mainly as an example of one of the longest words in the English language).