relativity
noun
rel·a·tiv·i·ty
ˌre-lə-ˈti-və-tē 
plural relativities
1
a
: 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
3
a
: 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
These two cases are stark reminders of the relativity of shareholder power in American companies, compared to the implicit power that resides with top management and boards.
—
Peter Vanham, Fortune, 8 Feb. 2024
High-energy muons traveling at near–light-speed endure longer, for milliseconds, because of the time dilation predicted by Einstein’s theory of relativity.
—Byadrian Cho, science.org, 28 Mar. 2024
See all Example Sentences for relativity 
Peter Vanham, Fortune, 8 Feb. 2024
High-energy muons traveling at near–light-speed endure longer, for milliseconds, because of the time dilation predicted by Einstein’s theory of relativity.
—Byadrian Cho, science.org, 28 Mar. 2024
See all Example Sentences for relativity
These examples are programmatically compiled from various online sources to illustrate current usage of the word 'relativity.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.
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“Relativity.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/relativity. Accessed 29 May. 2024.
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relativity
noun
rel·a·tiv·i·ty
ˌrel-ə-ˈtiv-ət-ē
plural relativities
1
: the quality or state of being relative
especially
: dependence on something else
2
a
: a theory in physics that considers mass and energy to be equal and that states that a moving object will experience changes in mass, size, and time which are related to its speed and are not noticeable except at speeds approaching that of light
b
: an extension of relativity theory to include gravity and its related acceleration effects
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