747: gay Dec 24, 2016

From a few decades old music to books and anything else from the past, it isn't too uncommon to find 'gay' as an adjective meaning, 'joyful', 'showy' or 'mirthful', as it did since the 12th century. In the 17th century, the word took on a second meaning of, 'drawn to pleasures' and sometimes, 'of loose or immoral lifestyle', but existed alongside the earlier sense. In the 19th century, 'gay' took on the meaning of 'prostitute' and a 'gay man' was one who slept with many prostitutes, giving rise to the phrase, 'gay it' to mean 'have sex'. Only in the 1920's or '30's did the word refer to what we think of today, and later on in the mid-50's gay men themselves felt that 'homosexual' was too clinical and cemented the definition which having so many senses up until then was sort of vague, so people stopped using 'gay' so mean 'jolly'. 'Gaiety' seems to have been unaffected and kept its original sense, however. See also "in the closet".