[1] : The Collaborative International Dictionary of English v.0.48

yawn \yawn\, n.
   1. an involuntary act, excited by drowsiness, etc.,
      consisting of a deep and long inspiration following
      several successive attempts at inspiration, the mouth,
      fauces, etc., being wide open.
      1913 webster

            one person yawning in company will produce a
            spontaneous yawn in all present.      --n. chipman.
      1913 webster

   2. the act of opening wide, or of gaping. --addison.
      1913 webster

   3. a chasm, mouth, or passageway. r.
      1913 webster

            now gape the graves, and trough their yawns let
            loose
            imprisoned spirits.                   --marston.
      1913 webster

[2] : The Collaborative International Dictionary of English v.0.48

yawn \yawn\ yaddn, v. i. imp.  p. p. yawned; p. pr. 
   vb. n. yawning. oe. yanien, yoghanien, ganien, gonien,
   as. g=anian; akin to ginian to yawn, gimacnan to yawn,
   open wide, g. gaumhnen to yawn, ohg. gin=en, gein=on,
   icel. gimacna to yawn, gin the mouth, oslav. zijati to
   yawn, l. hiare to gape, yawn; and perhaps to e. begin, cf.
   gr. cheia` a hole. root47b. cf. begin, gin to begin,
   hiatus.
   1913 webster
   1. to open the mouth involuntarily through drowsiness,
      dullness, or fatigue; to gape; to oscitate. "the lazy,
      yawning drone." --shak.
      1913 webster

            and while above he spends his breath,
            the yawning audience nod beneath.     --trumbull.
      1913 webster

   2. to open wide; to gape, as if to allow the entrance or exit
      of anything.
      1913 webster

            't is now the very witching time of night,
            when churchyards yawn.                --shak.
      1913 webster

   3. to open the mouth, or to gape, through surprise or
      bewilderment. --shak.
      1913 webster

   4. to be eager; to desire to swallow anything; to express
      desire by yawning; as, to yawn for fat livings. "one long,
      yawning gaze." --landor.
      1913 webster
see also:
yawned yawning hiatus 

[3] : WordNet (r) 2.0

yawn
     n : an involuntary intake of breath through a wide open mouth;
         usually triggered by fatigue or boredom; "he could not
         suppress a yawn"; "the yawning in the audience told him
         it was time to stop"; "he apologized for his ostinancy"
         syn: yawning, oscitance, oscitancy
     v 1: utter a yawn, as from lack of oxygen or when one is tired;
          "the child yawned during the long performance"
     2: be wide open; "the deep gaping canyon" syn: gape, yaw
see also:
yawning oscitance oscitancy gape yaw 

[4] : Moby Thesaurus II by Grady Ward, 1.0

56 moby thesaurus words for "yawn":
   aperture, boredom, broaching, cavity, chasm, check, clearing,
   cleft, crack, dehisce, dehiscence, disclosure, doldrums, doze,
   drowse, ennui, fenestra, fistula, fontanel, foramen, gap, gape,
   gaping, gat, gulf, hang open, hiatus, hole, hollow, inlet,
   interval, lacuna, laying open, leak, nap, opening, opening up,
   orifice, oscitancy, oscitate, oscitation, outlet, pandiculation,
   passageway, pore, slot, snooze, space, split, stoma, the gapes,
   throwing open, uncorking, unstopping, yaw, yawning

Yawn >> Y Words
Yawn, definition of term: Yawn
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