The Collaborative International Dictionary of English v.0.48:
Eater \Eat"er\ ([=e]t"[~e]r), n. One who, or that which, eats. [1913 Webster]WordNet (r) 3.0 (2006):
eater n 1: someone who consumes food for nourishment [syn: eater, feeder] 2: any green goods that are good to eat; "these apples are good eaters"