adj

• Homosexual:
  "Cliff is gay, but his twin brother is straight."
• Homosexual:
  "gay and lesbian people"
• Homosexual:
  "In fact, as several letter writers to the New York Times pointed out in their response to the article, the disjuncture between these two popularized penguins shows how radically separated from each other are communities of gay people and communities of right-wing religious conservatives: if the Christian fundamentalists had looked up "gay penguins" or even "penguins" on the Internet, they would have encountered several gay penguin sites, including the story of Roy and Silo, the Central Park Zoo gay penguin couple about whom a children's book was written; the saga of the gay penguin community at a German zoo; and the campaign of Gay Penguin for President (whose slogan was "George W. Bush talks the talk, but Gay Penguin walks the walk.")"
• Homosexual:
  "Although the number of gay weddings has increased significantly, many gay and lesbian couples — like many straight couples — are not interested in getting married."

noun

• (now chiefly in the plural) A homosexual, especially a male homosexual.
  "[headline] N.Y. Gays: Will the Spark Die?"
• (informal, often derogatory or ironic) Gayness: the quality of being gay.
  "Anti-gay persecution holds that you can pray the gay out of a person, or scare it out of them, or cajole it out of them."
• (dialectal, obsolete) Something which is bright or colorful, such as a picture or a flower.
  "At a stall soon Mary bote / A hume-book full ov gays."
• (obsolete) An ornament, a knick-knack.
  "Look upon precepts in emblems, as they do to upon gays and pictures."

verb

• (transitive, dated, uncommon) To make happy or cheerful.
  "SAYING GOOD-BYE (song) WE are always saying / "Good-bye, good-bye! / In work, in playing, / In gloom, in gaying […]"
• (transitive, uncommon) To cause (something, e.g. AIDS) to be associated with homosexual people.

adv

• (Scotland, Northern England) Considerably, very.
  "And, tho' his guts ware lank and toom, / They're twice as big's this gay big room."