dark matter

noun

: nonluminous matter not yet directly detected by astronomers that is hypothesized to exist to account for various observed gravitational effects

Examples of dark matter in a Sentence

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PBHs have also been considered as a possible constituent of dark matter, the invisible matter permeating the universe that outweighs normal matter by a factor of about five. Phil Plait, Scientific American, 27 Mar. 2026 The claim, remember, is that these cosmic voids are completely empty of normal matter, dark matter, and emit no detectable radiation of any kind. Big Think, 26 Mar. 2026 If all goes according to plan, Roman will be able to map structures on cosmic scales, measure dark energy and dark matter throughout the universe, detect distant black holes and potentially discover tens of thousands of alien planets. Brett Tingley, Space.com, 26 Mar. 2026 This extreme depth shields the detectors from cosmic rays and other background radiation that could obscure potential dark matter signals. Georgina Jedikovska, Interesting Engineering, 18 Mar. 2026 See All Example Sentences for dark matter

Word History

First Known Use

1933, in the meaning defined above

Time Traveler
The first known use of dark matter was in 1933

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Cite this Entry

“Dark matter.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/dark%20matter. Accessed 29 Mar. 2026.

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