time dilation

noun

Definition of time dilation 

: a slowing of time in accordance with the theory of relativity that occurs in a system in motion relative to an outside observer and that becomes apparent especially as the speed of the system approaches that of light

called also time dilatation

Examples of time dilation in a Sentence

Recent Examples on the Web

There is a phenomenon of relativity known as time dilation, in which time appears to slow down almost to a stop for bodies that approach the speed of light. Jerry Adler, Newsweek, "Stephen Hawking, Master of the Universe: Our 1988 Cover Story on the Legendary Physicist," 14 Mar. 2018

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

First Known Use of time dilation

1934, in the meaning defined above

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The first known use of time dilation was in 1934

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More from Merriam-Webster on time dilation

Britannica.com: Encyclopedia article about time dilation

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