To open the mouth wide, especially involuntarily, as in a yawn, anger, or surprise.
To stare in wonder.
To open wide; to display a gap.
Of a cat: to open the passage to the vomeronasal organ, analogous to the flehming in other animals.
Wide open.
There’s a gaping hole in the fence.
The act of one who gapes.
Something gaping; something agape.