naff is a rather old fashioned English expression meaning dorky or geeky or unfashionable. I never use it in Atlantic City. But we did say that things were "gay" to mean stupid or unfashionable.

I was surprised to hear my daughter using the word "gay" in exactly the same way as i did when I was growing up in America, because it is a whole generation later and she is growing up 3000 miles from where I did.

As a completely seperate issue, Polari is a UK thing. It was a slang gay people used to identify and communicate with one another when being gay was still illegal in the UK, and it became part of the culture. Some of the words are supposed to have come from Romany, and some are simply back to front, like "riah" for hair.