yawnyɔn(v.i.)

1. to open the mouth somewhat involuntarily with a prolonged, deep inhalation and sighing or heavy exhalation, as from drowsiness or boredom.

   Category: Physiology

2. to extend or stretch wide, as an open and deep space.

3. (v.t.)to say with a yawn.

4. (n.)an act or instance of yawning.

5. a deep, open space; chasm.

6. a bored reaction. something so boring as to make one yawn.

   Category: Common Vocabulary, Informal

   Ref: Also called yawner.

Origin of yawn:

bef. 900; ME yanen, yonen, OE ge(o)nian; akin to OE gānian, ginan, OHG ginōn, ON gīna to yawn, and to chasm , hiatus

yawn′ing•ly(adv.)