Gay is a term that primarily refers to a homosexual person or the trait of being homosexual. The term originally meant 'carefree', 'cheerful', or 'bright and showy'.
While scant usage referring to male homosexuality dates to the late 19th century, that meaning became increasingly common by the mid-20th century. In modern English, gay has come to be used as an adjective, and as a noun, referring to the community, practices and cultures associated with homosexuality. In the 1960s, gay became the word favored by homosexual men to describe their sexual orientation. By the end of the 20th century and beginning of the 21st century, the word gay was recommended by major LGBT groups and style guides to describe people attracted to members of the same sex, although it is more commonly used to refer specifically to men.
At about the same time, a new, pejorative use became prevalent in some parts of the world. Among younger speakers, the word has a meaning ranging from derision (e.g., equivalent to 'rubbish' or 'stupid') to a light-hearted mockery or ridicule (e.g., equivalent to 'weak', 'unmanly', or 'lame'). The extent to which these usages still retain connotations of homosexuality has been debated and harshly criticized.
The word gay arrived in English during the 12th century from Old French gai, most likely deriving ultimately from a Germanic source.
In English, the word's primary meaning was "joyful", "carefree", "bright and showy", and the word was very commonly used with this meaning in speech and literature. For example, the optimistic 1890s are still often referred to as the Gay Nineties. The title of the 1938 French ballet Gaîté Parisienne ("Parisian Gaiety"), which became the 1941 Warner Brothers movie, The Gay Parisian, also illustrates this connotation. It was apparently not until the 20th century that the word began to be used to mean specifically "homosexual", although it had earlier acquired sexual connotations.
The derived abstract noun gaiety remains largely free of sexual connotations and has, in the past, been used in the names of places of entertainment, such as the Gaiety Theatre in Dublin.