The word gay has maintained three main functions throughout the twentieth century, namely
(adj.) Happy, jolly.
(n.) a homosexual male (and also sometimes used for a female) who is happy (gay) with thier sexual orientation.
(adj.) or (v.) to be or act gay, to do something stupid, taking the second definition as an insult, usually to a hetrosexual, especially a homophobe
or one wary of homosexual men under the (might I add wrong) impression that the male wishes to bugger them.
a) "...those were gay old times...."-Mr Burns
A: "I hear that John is gay, is that true?"
B: "No, he's just a pink pretender out for the ladies..."
c) "Dude, eating your snot is soooo gay"
"Yo mama likes the gay man" "STFU"
"You're gay, gayboy" "You're the gaylord"
"That dog is gay"
"Look at that gay sodomite over there"