Champ at the bit

What is Champ at the bit?

Champ at the bit definition and meaning on Dictionary terms:
verb (used with object)
to bite upon or grind, especially impatiently: The horses champed the oats.
to crush with the teeth and chew vigorously or noisily; munch.
to mash; crush.

verb (used without object)
to make vigorous chewing or biting movements with the jaws and teeth.

the act of champing.