gay

The word 'gay' entered English in the late 12th century from Old French 'gai', meaning "joyful, happy, pleasant, carefree." Its ultimate origin is uncertain but may be from a Germanic source. For centuries, its primary meaning was "light-hearted, exuberantly cheerful, bright or showy." By the late 17th century, it developed a sense of "addicted to pleasure, immoral," which led to its 20th-century use as a slang term for a homosexual person, initially implying a promiscuous lifestyle. This slang usage became the dominant, neutral, and standard meaning in the latter half of the 20th century, while its older meanings became largely archaic or dated.

The word 'gay' is a simplex word of Old French origin. It cannot be meaningfully segmented into smaller morphemes based on its modern English spelling.