yawning

n. act of open the mouth wide and taking a deep breath (involuntarily - from tiredness or boredom)

v. involuntarily open the mouth wide and inhale due to drowsiness or fatigue

A yawn (synonyms chasma, pandiculation, oscitation from the Latin verb oscitare, to open the mouth wide ) is a reflex of deep inhalation and exhalation associated with tiredness, stress, over-work, lack of stimulation, or boredom. Pandiculation is the term for the act of stretching and yawning. Yawning is a powerful non-verbal message with several possible meanings, depending on the circumstances. Another speculated reason for yawning is nervousness and is also claimed to help increase the state of alertness of a person - paratroopers were noted yawning right before their first jump. The exact causes of yawning are still undetermined.
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Yawning a deep, involuntary inspiration with the mouth open, often accompanied by the act of stretching. [more]Yawning - Community and Resources

Noun
1. 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"
(synonym) yawn, oscitance, oscitancy
(hypernym) reflex, instinctive reflex, innate reflex, inborn reflex, unconditioned reflex, physiological reaction
(hyponym) pandiculation
(derivation) yawn
Adjective
1. gaping open as if threatening to engulf someone or something; "the yawning mine shaft"; "a yawning abyss"
(similar) open
2. with the mouth wide open indicating boredom or sleepiness; "a yawning congregation"
(similar) open, opened
3. showing lack of attention or boredom; "the yawning congregation"
(synonym) drowsy, oscitant, yawning(a)
(similar) inattentive

Noun
1. 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"
(synonym) yawning, oscitance, oscitancy
(hypernym) reflex, instinctive reflex, innate reflex, inborn reflex, unconditioned reflex, physiological reaction
(hyponym) pandiculation
Verb
1. utter a yawn, as from lack of oxygen or when one is tired; "The child yawned during the long performance"
(hypernym) breathe, take a breath, respire, suspire
(derivation) yawning, oscitance, oscitancy
2. be wide open; "the deep gaping canyon"
(synonym) gape, yaw
(hypernym) be

(p. pr. & vb. n.)
of Yawn