- (uncountable) A disease in poultry caused by gapeworm in the windpipe, a symptom of which is frequent gaping.
- A large opening.
- (zoology) The maximum opening of the mouth (of a bird, fish, etc.) when it is open.
- (uncommon) An act of gaping; a yawn.
- The width of an opening.
- (intransitive) To open wide; to display a gap.
- (intransitive) To stare in wonder.
- (intransitive) To open the mouth wide, especially involuntarily, as in a yawn, anger, or surprise.