'Cud' in the Bible

Every animal that parts the hoof, and has the hoof cloven in two, [and] chews the cud, among the animals, that may you eat.

Nevertheless these you shall not eat of them that chew the cud, or of those who have the hoof cloven: the camel, and the hare, and the rabbit; because they chew the cud but don't part the hoof, they are unclean to you.

The pig, because it has a split hoof but doesn't chew the cud, is unclean to you: of their flesh you shall not eat, and their carcasses you shall not touch.