To open the mouth involuntarily or as the result of weariness, sleepiness, or absorbed attention; yawn.According to the inducing cause of the gaping, the verb, without losing its literal meaning, usually takes on an additional specific sense.To yawn from sleepiness, weariness, or dullness.To open the mouth for food, as young birds.Hence — To open the mouth in eager expectation; expect, await, or hope for, with the intent to receive or devour. See phrases below.To stand with open mouth in wonder, astonishment, or admiration; stand and gaze; stare. See phrases below, and gaping.To open as a gap, fissure, or chasm; split open; become fissured; show a fissure.To stand in eager expectation of; covet; desire; long for.To covet, desire; long for.Synonyms Gaze, etc. See stare.n. The act of gaping.n. A fit of yawning: commonly in the plural.n. In zoology:n. The width of the mouth when opened; the interval between the upper and under mandibles; the rictus, or commissural line. See first cut under bill.n. The gap or interval between the valves of a bivalve mollusk where the edges of the valves do not fit together when the shell is shut. See gaper, 4.n. plural A disease of young poultry, caused by the presence of a nematoid worm or strongyle (Syngamus trachealis) in the windpipe, attended by frequent gaping as a symptom.