The Collaborative International Dictionary of English v.0.48:

Gay \Gay\ (g[=a]), a. [Compar. Gayer; superl. Gayest.] [F.
   gai, perhaps fr. OHG. g?hi swift, rapid, G. g[aum]h, j[aum]h,
   steep, hasty; or cf. OHG. w?hi beatiful, good. Cf. Jay.]
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   1. Excited with merriment; manifesting sportiveness or
      delight; inspiring delight; livery; merry.
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            Belinda smiled, and all the world was gay. --Pope.
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            Gay hope is theirs by fancy fed.      --Gray.
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   2. Brilliant in colors; splendid; fine; richly dressed.
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            Why is my neighbor's wife so gay?     --Chaucer.
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            A bevy of fair women, richly gay
            In gems and wanton dress!             --Milton.
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   3. Loose; dissipated; lewd. [Colloq.]

   Syn: Merry; gleeful; blithe; airy; lively; sprightly,
        sportive; light-hearted; frolicsome; jolly; jovial;
        joyous; joyful; glad; showy; splendid; vivacious.
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