yawning

gaping open as if threatening to engulf someone or something; "the yawning mine shaft"; "a yawning abyss"

with the mouth wide open indicating boredom or sleepiness; "a yawning congregation"

showing lack of attention or boredom; "the yawning congregation"

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 oscitancy"