[1] : 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 

[2] : WordNet (r) 2.0

yawning
     adj 1: gaping open as if threatening to engulf someone or
            something; "the yawning mine shaft"; "a yawning abyss"
     2: with the mouth wide open indicating boredom or sleepiness;
        "a yawning congregation"
     3: showing lack of attention or boredom; "the yawning
        congregation" syn: drowsy, oscitant, yawninga
     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: yawn, oscitance, oscitancy
see also:
drowsy oscitant yawninga yawn oscitance oscitancy 

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

76 moby thesaurus words for "yawning":
   abysmal, abyssal, agape, ajar, anesthetized, bottomless,
   cataleptic, cavernous, comatose, deep as hell, dehiscence,
   dehiscent, doped, doziness, dozy, dreamy, drowsiness, drowsy,
   drugged, drugged with sleep, fathomless, gape, gaping, half asleep,
   heaviness, heavy, heavy with sleep, heavy-eyed, in a stupor,
   languid, languor, lethargic, lethargy, napping, narcoleptic,
   narcose, narcotized, narcous, nodding, openmouthed, oscitancy,
   oscitant, oscitation, out of it, pandiculation, plumbless,
   plunging, ringent, sedated, slack-jawed, sleep-drowned,
   sleep-drunk, sleep-filled, sleep-swollen, sleepful, sleepiness,
   sleepy, slumberous, slumbery, snoozy, somnolence, somnolency,
   somnolent, soporific, soundless, stretching, stretchy, stuporose,
   stuporous, the gapes, unfathomable, unfathomed, unsounded,
   without bottom, yawn, yawny

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