1 a hard round fruit that has red, light green, or yellow skin and is white inside: apple pie an apple tree2be the apple of somebody’s eye to be loved very much by someone: Ben was always the apple of his father’s eye.3be as American as apple pie to be typically or completely American: The group’s optimism is as American as apple pie.4the apple doesn’t fall far from the tree used to say that children are usually similar to their parents, especially in a bad way [Origin: Old English æppel] → see alsoAdam's apple, bob for applesat bob1 (5), a rotten appleat rotten1 (6), upset the apple cartat upset2 (6)