rel·​a·​tiv·​i·​ty | \ ˌre-lə-ˈti-və-tē How to pronounce relativity (audio) \
plural relativities

Definition of relativity

1a : the quality or state of being relative
b : something that is relative
2 : the state of being dependent for existence on or determined in nature, value, or quality by relation to something else
3a : a theory which is based on the two postulates (1) that the speed of light in a vacuum is constant and independent of the source or observer and (2) that the mathematical forms of the laws of physics are invariant in all inertial systems and which leads to the assertion of the equivalence of mass and energy and of change in mass, dimension, and time with increased velocity

called also special relativity, special theory of relativity

b : an extension of the theory to include gravitation and related acceleration phenomena

called also general relativity, general theory of relativity

Examples of relativity in a Sentence

Recent Examples on the Web The observations also give scientists the opportunity to test Einstein’s theory of relativity. Brendan Byrne, Smithsonian Magazine, 12 May 2022 The automobile and telephone were coming into wide use and electrical power grids were revolutionizing city life, while the world of ideas was being transformed by Freudian psychology and Einstein’s theory of relativity. Susan Delson, WSJ, 29 Apr. 2022 Our ability to consider space in this way is consistent with Einstein’s theory of relativity, which itself explains the limit on how fast objects can travel through space. Scientific American, 16 Aug. 2021 According to Einstein’s theory of relativity, energy and mass are equivalent, so what happens is that the energy of the electric field can temporarily convert into a pair of particles, one matter and one antimatter. Don Lincoln, Forbes, 17 Apr. 2021 Holographic duality could help link standard model and relativity physics for good. Caroline Delbert, Popular Mechanics, 7 Mar. 2022 General relativity also doesn’t explain the future of the universe. Quanta Magazine, 23 Feb. 2022 My slow pace at full effort teaches me that our running performances are always about relativity–run better than last week, last year; beat your rivals, the record, or your PR. Roger Robinson, Outside Online, 21 Dec. 2021 Among other things, Giacometti’s art appears to embody the era in which theories of relativity changed understandings of time and space forever. Steven Litt, cleveland, 20 Mar. 2022 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'relativity.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of relativity

circa 1834, in the meaning defined at sense 1a

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Time Traveler for relativity

Time Traveler

The first known use of relativity was circa 1834

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Last Updated

17 May 2022

Cite this Entry

“Relativity.” Dictionary, Merriam-Webster, Accessed 24 May. 2022.

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