gay 
(gā)
(gā)adj. gay·er, gay·est
1. Of, relating to, or having a sexual orientation to persons of the same sex.
2. Showing or characterized by cheerfulness and lighthearted excitement; merry.
3. Bright or lively, especially in color: a gay, sunny room.
4. Offensive Slang Socially inappropriate or foolish.
5. Given to social pleasures, especially at the expense of serious pursuits: "You know she is gay, and wild, loves company and mirth, and that it was her impatience of restraint in these things, that made the breach between her and her father" (Daniel Defoe).
6. Dissolute or licentious: "He and his wife led a gay life. He made money fast, and she spent it faster. Eventually, both were broken physically" (Robert Coleman).
n.
1. A person whose sexual orientation is to persons of the same sex.
2. A man whose sexual orientation is to men: an alliance of gays and lesbians.
[Middle English gai, lighthearted, brightly colored, from Old French, possibly of Germanic origin.]
gayness n.
Usage Note: The word gay is now standard in its use to refer to people whose sexual orientation is to the same sex, in large part because it is the term that most gay people prefer in referring to themselves. Although gay can refer to both sexes, often it is used to refer solely to males. When the intended meaning is not contextually evident, the phrases gay and lesbian or lesbian and gay are commonly used. Gay is generally considered objectionable when used as a noun to refer to particular individuals, as in There were two gays on the panel; here phrasing such as Two members of the panel were gay is preferable. But there is no objection to the use of the noun in the plural to refer collectively either to gay men or to gay men and lesbians, so long as it is clear whether men alone or both men and women are being discussed.