Source : Webster's Revised Unabridged Dictionary (1913)

Joke \Joke\, n. [L. jocus. Cf {Jeopardy}, {Jocular}, {Juggler}.]
   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.

            And gentle dullness ever loves a joke. --Pope.

            Or witty joke our airy senses moves To pleasant
            laughter.                             --Gay.

   2. Something not said seriously, or not actually meant;
      something done in sport.

            Inclose whole downs in walls, 't is all a joke.
                                                  --Pope.

   {In joke}, in jest; sportively; not meant seriously.

   {Practical joke}. See under {Practical}.