I think what he meant was when the term 'gay' is thrown around to just mean something insulting as opposed to meaning 'homosexual'. I know that happens a lot in my school and it bugs me a lot.
*gets homework* "what? homework blud? thats like, so gay innit"
I don't like having that word being spoken around me like that, either, but there's only so much you can do to prevent it. :/