Aquele caralho já me está a chatear. - That fuck is getting on my nerves.
2."brazilian slang, a very handy word to express pretty much any sort of emotion when starting up a sentence. NOT to be used in any formal situation or around formal people, unless you want their undivided attention". (shamelessly stolen parts of a small blog)
3.used at the end of a sentence, in order to imply an undefined amount of intensity to some subject/action.