practical joke
    n 1: a prank or trick played on a person (especially one
         intended to make the victim appear foolish)

Joke \Joke\, n. [L. jocus. Cf Jeopardy, Jocular, Juggler.]
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   1. Something said for the sake of exciting a laugh; something
      witty or sportive (commonly indicating more of hilarity or
      humor than jest); a jest; a witticism; as, to crack
      good-natured jokes.
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            And gentle dullness ever loves a joke. --Pope.
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            Or witty joke our airy senses moves
            To pleasant laughter.                 --Gay.
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   2. Something not said seriously, or not actually meant;
      something done in sport.
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            Inclose whole downs in walls, 't is all a joke.
                                                  --Pope.
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   In joke, in jest; sportively; not meant seriously.

   Practical joke. See under Practical.
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Practical \Prac"ti*cal\, a. [L. practicus active, Gr. ? fit for
   doing or performing, practical, active, fr. ? to do, work,
   effect: cf. F. pratique, formerly also practique. Cf.
   Pragmatic, Practice.]
   1. Of or pertaining to practice or action.
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   2. Capable of being turned to use or account; useful, in
      distinction from ideal or theoretical; as, practical
      chemistry. "Man's practical understanding." --South. "For
      all practical purposes." --Macaulay.
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   3. Evincing practice or skill; capable of applying knowledge
      to some useful end; as, a practical man; a practical mind.
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   4. Derived from practice; as, practical skill.
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   Practical joke, a joke put in practice; a joke the fun of
      which consists in something done, in distinction from
      something said; esp., a trick played upon a person.
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