1. To open the mouth involuntarily through drowsiness, dullness, or fatigue; to gape; to oscitate. The lazy, yawning drone. And while above he spends his breath, The yawning audience nod beneath. (Trumbull)
Origin: OE. Yanien, yanien, ganien, gonien, AS. Ganian; akin to ginian to yawn, ginan to yawn, open wide, G. Gahnen to yawn, OHG. Ginen, geinon, Icel. Gina to yawn, gin the mouth, OSlav. Zijati to yawn, L. Hiare to gape, yawn; and perhaps to E. Begin, cf. Gr. Cheia a hole. B. Cf. Begin, Gin to begin, Hiatus.