par·​sec | \ ˈpär-ˌsek How to pronounce parsec (audio) \

Definition of parsec

: 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

Recent Examples on the Web This is a huge region; for comparison, ten kiloparsec is about the radius of a typical spiral galaxy like our own Milky Way, and a parsec itself is already pretty big, at more than three light-years. Stephon Alexander, Wired, 31 Aug. 2021 Recently astronomers settled on a value of 25 parsecs (82 light-years) above the plane, but our results strongly disagree with this estimate. Mark J. Reid, Scientific American, 17 Mar. 2020 The problem comes in the final parsec, where gravity is not strong enough to overcome the centrifugal force of each black hole’s orbit to pull the pair closer together. Nola Taylor Redd, Scientific American, 10 Feb. 2020 In this new version, Greedo pulls the trigger first in a wild shot, missing Han by half a parsec. Alex Horton, Washington Post, 13 Nov. 2019 The image shows the supermassive black hole at the centre of the galaxy Messier 87, which lies around 17 parsecs (55 million light years) from Earth. Zeeya Merali, Scientific American, 5 Sep. 2019 A parsec is a unit of distance, not time, so why would Solo use it to explain how quickly his ship could travel? Kyle Hill, WIRED, 12 Feb. 2013 See More

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

First Known Use of parsec

1913, in the meaning defined above

History and Etymology for parsec

parallax + second

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Cite this Entry

“Parsec.” Dictionary, Merriam-Webster, Accessed 22 May. 2022.

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