relativity theory re·la·ti·vitytheory uncommon noun 1. (physics) the theory that space and time are relative concepts rather than absolute concepts Synonymsrelativitytheory of relativityrelativity theoryEinstein's theory of relativity Related words Broader terms scientific theory Narrower terms general relativityspecial relativity WordNet 2.1 (Princeton University). WordNet 2.1 Copyright Princeton University. All rights reserved.
