relativity

noun

1. The state of being relative to something else; the absence of universally applicable rules or standards; relativism; (countable) an instance of this.

2. physicsShort for principle of relativity ("the principle that the laws of physics should be the same for all observers").

3. specificallyAlso Einsteinian relativity: the reliance of the nature of physical phenomena (such as gravity, light, mass, and time) on the relative motion between an observer and the thing observed, as developed by Albert Einstein in two theories, special relativity and general relativity.

4. chiefly in the pluralAn evaluation of the similarities and differences between things; a comparison; hence, a difference in position or status between things; a disparity.

5. economicsspecificallyThe difference in pay or positions between different employees in a business (internal relativity), or between different businesses (external relativity); a differential.

6. (physics) the theory that space and time are relative concepts rather than absolute concepts

   Similar: theory of relativity, relativity theory, Einstein's theory of relativity

7. The quality of being relative and having significance only in relation to something else