parsec

noun

par·​sec ˈpär-ˌsek How to pronounce parsec (audio)
: a unit of measure for interstellar space that is equal to 3.26 light-years and is the distance to an object having a parallax of one second as seen from points separated by one astronomical unit

Examples of parsec in a Sentence

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These gravitational waves most likely come from tightly orbiting supermassive black holes within a parsec of each other that are close to merging. — Jonathan O’Callaghan, WIRED, 1 Dec. 2024 To wrap your mind around that distance, 1 parsec is equal to 3.26 light years or about 206,265 times the distance from Earth to the Sun. — Justin Ray, Robb Report, 14 June 2023

Word History

Etymology

parallax + second

First Known Use

1913, in the meaning defined above

Time Traveler
The first known use of parsec was in 1913

Rhymes for parsec

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Cite this Entry

“Parsec.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/parsec. Accessed 25 Mar. 2025.

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Britannica.com: Encyclopedia article about parsec

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