Anything a dinosaur bites that is hard and a tooth impression or teeth impressions is left is known as a bite mark.  By looking at a bite mark and noting the spacing between the teeth, the alignment of the teeth and the size of the impressions, one can possibly identify the owner.  These markings can tell us what the predator fed on or maybe what they scavenged on, since the fossil record can not tell us whether the marks were made when the prey  was alive or already dead.