Shortened version of ' IS IT NOT '. A question, probably, when originally shortened, but now used by English people in about every fucking sentence they say . Half the time it's used as a response, where most people might say 'yes/yeah' or 'really/wow' or 'damn/shit' ... init/ innit is used.

ME - 'I went to the store'U - 'innit'Me - ' Bought some milk and bread and smokes and went home, watched BB on TV'U - 'innit'" So me was out with me boys, innit , and we was going to get some beers, innit, when this guy, yeah, like comes up to us, yeah, innit, and he was like Gimme some change, we was like, innit"