Green’s Dictionary of Slang

1. a bite, a mouthful.

1966		T. Keyes All Night Stand 89: Fat kraut who can think of nothing better than to give a great chomp at her breast.
1970		J. Carroll ‘The Basketball Diaries’ in Paris Review Fall 97: [S]ometimes we’re not so lucky with that mutt and it will tear the leg of your pants off in one chomp, perhaps a good part of your ass with it.
2001		S. King Dreamcatcher 128: Something small, but with big teeth, would soon spring at him, taking a great big chomp out of his balls.

2. food.

1992

R.G. Barrett White Shoes 109: The ‘chomp’ was equal to the surroundings.