Pronunciation: (yôn),[key] —v.i. 1. to open the mouth somewhat involuntarily with a prolonged, deep inhalation and sighing or heavy exhalation, as from drowsiness or boredom.
2. to open wide like a mouth.
3. to extend or stretch wide, as an open and deep space.
—v.t. 1. to say with a yawn.
2. Archaic.to open wide, or lay open, as if by yawning.
—n. 1. an act or instance of yawning.
2. an opening; open space; chasm.
3. Also,yawner.Informal.something so boring as to make one yawn: Critics say the new fashions are one big yawn.