<mathematics> A bijective map between two objects which preserves, in both directions, any structure under consideration. Thus a `group isomorphism' preserves group structure; an order isomorphism (between posets) preserves the order relation, and so on. Usually it is clear from context what sort of isomorphism is intended.
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Nearby terms: isometric joystick « isometry « isomorphic « isomorphism » isomorphism class » ISO Pascal » ISO seven layer model