time dilation


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 And because of the time dilation effects in Albert Einstein’s theory of gravity, known as general relativity, 1 year passing on such a planet would see thousands of years go by around an ordinary star. Daniel Clery, Science | AAAS, "Could a habitable planet orbit a black hole?," 4 Feb. 2020 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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Time Traveler

The first known use of time dilation was in 1934

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Statistics for time dilation

Last Updated

8 Feb 2020

Cite this Entry

“Time dilation.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/time%20dilation. Accessed 5 Apr. 2020.

More from Merriam-Webster on time dilation

Britannica.com: Encyclopedia article about time dilation

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