oscitance

nouns

drowsiness and dullness manifested by yawning
oscitance, oscitancy
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"
oscitance, oscitancy, yawn, yawning