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 That means the time dilation has practically zero effect. Rhett Allain, Wired, "So Can Flash Actually Run Faster Than the Speed of Light?," 2 Apr. 2021 Back on Earth, Eyehategod’s music at least feels like a metaphor for gravitational time dilation. Washington Post, "Eyehategod’s high-gravity metal can connect you to the heavens," 12 Mar. 2021 Due to relativistic time dilation, at that speed, the OMG particle could travel to our nearest neighbor star, Proxima Centauri, in 0.43 milliseconds of the particle's own time. Rebecca Coffey, Forbes, "How Cosmic Rays Help Scientists Tell How Old Dead Stuff Is: An Exuberant, Plain Language Primer On Radiocarbon Dating, in 20 Facts," 3 Mar. 2021 Because of a phenomenon called cosmological time dilation, due to the expansion of the universe, the crash will seem to take place in 21 years from our point of view on Earth. Clara Moskowitz, Scientific American, "Giant Black Holes May Be on a Collision Course," 22 May 2015 Due to time dilation, those messages could reveal the entire sweep of future history. WIRED, "Black Holes Aren’t As Bad As You Think," 28 Nov. 2020 Though the effect is far too small to be noticeable to humans, this idea of quantum time dilation could have repercussions for high-precision quantum clocks. Jonathan O'callaghan, Scientific American, "Quantum Time Twist Offers a Way to Create Schrödinger’s Clock," 23 Oct. 2020 All the matter that fell in after the astronaut over millions of years would come crashing down on them in less than a second because of the extreme time dilation effects. Jennifer Ouellette, Ars Technica, "Death by black hole: Astronomers spot flare from “spaghettification” of star," 12 Oct. 2020 In one such experiment, the lifetime of muon decay verifies the existence of time dilation. Ronald C. Lasky, Scientific American, "Does Time Tick at the Same Rate for Everyone?," 24 Oct. 2014

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.

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First Known Use of time dilation

1934, in the meaning defined above

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Time Traveler for time dilation

Time Traveler

The first known use of time dilation was in 1934

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Statistics for time dilation

Last Updated

9 Apr 2021

Cite this Entry

“Time dilation.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/time%20dilation. Accessed 22 Apr. 2021.

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More from Merriam-Webster on time dilation

Britannica.com: Encyclopedia article about time dilation

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