2. Uncool, crappy, lame
2. A derogatory term often used too widely by mostly ignorant and prejudiced people, but sometimes used correctly (for example on South Park by Trey Parker and Matt Stone) to describe something lacking force, power or coolness because it is either phony and fake, or talentless, therefore rendering it lame and crappy.
This meaning is derived from the fact that to a strongly heterosexual person, the thought of sex with their own sex is repulsive, (regardless of how much they might love and respect any gay friends) and always will be. So when say for example a song or movie or TV show is considered 'gay' it expresses a feeling of revulsion because it is so full of lies, bad acting, false emotion, sentimentality, a cringeworthy lack of inspiration etc that trying to embrace and enjoy it by analogy is like trying sex with a dude when you're a straight guy.
Therefore this meaning is inherently prejudiced in origin against homosexuals, so should be used with restraint, but can be effective and hilarious when used correctly.
1 I knew that guy was gay, he just didn't seem that interested when we would talk about the hottest girls
2. Have you heard that new song by U2? it's totally gay, and they used to be so good...
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