As a Noun:
1. A homosexual man. An offensive sign, used to show disapproval or contempt. British English = poof, fairy. Australian English = poofter, fairy. American English = fag, fairy.
As a Verb or Adjective:
1. Of a man, to behave in a way which is thought to be like a woman. English = (be) effeminate.
2. Of a man, to behave in a way which is thought to be like the cultural stereotype of a homosexual. Idiomatic English = (be) camp.
3. Of anyone, to behave in a way that uses exaggerated gestures.