The Collaborative International Dictionary of English v.0.48:

Puck \Puck\, n. [OE. pouke; cf. OSw. puke, Icel. p[=u]ki an evil
   demon, W. pwca a hobgoblin. Cf. Poker a bugbear, Pug.]
   1. (Medi[ae]val Myth.) A celebrated fairy, "the merry
      wanderer of the night;" -- called also Robin Goodfellow,
      Friar Rush, Pug, etc. --Shak.
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            He meeteth Puck, whom most men call
            Hobgoblin, and on him doth fall.      --Drayton.
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   2. (Zool.) The goatsucker. [Prov. Eng.]
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