red giant


Definition of red giant

: a star that has low surface temperature and a diameter that is large relative to the sun

Examples of red giant in a Sentence

Recent Examples on the Web The researchers concluded that the red giant appears to be dancing with an unseen partner., "‘Unicorn’ Discovery Points to a New Population of Black Holes," 27 Jan. 2021 This year was all about Betelgeuse, a red giant star in the Orion constellation thought to be on the brink of a supernova explosion. Ashley Strickland, CNN, "The year 2020 in space discoveries," 24 Dec. 2020 This gives the red giant a radius 750 times that of our sun. Ashley Strickland, CNN, "Betelgeuse, the unusually dimming star, is smaller and closer than scientists thought," 19 Oct. 2020 In a few billion years, our own sun will swell up to a red giant, shedding enough stellar material that its gravitational hold on its planets will weaken, allowing some to wander away. Nola Taylor Redd, Smithsonian Magazine, "How NASA’s New Telescope Will Help Astronomers Discover Free-Floating Worlds," 30 Sep. 2020 At that time, the sun will expand into a red giant star, subsuming the Earth in a fiery blaze. Madeleine Stone, National Geographic, "Earth is setting heat records. It will be much hotter one day.," 20 Aug. 2020 In 2017, astronomers were stunned when a red giant star 22 million light-years away in the Fireworks Galaxy suddenly disappeared. Jennifer Leman, Popular Mechanics, "How Could a Massive Star Just Vanish Without a Trace?," 6 July 2020 This causes the entire star to bloat out into what’s known as a red giant. Mike Lynch, Twin Cities, "Skywatch: There’s a star in all of us," 15 Dec. 2019 At some point, these stars have exhausted the lighter elements that fueled their earlier existence, flared up into a bloated red giant, and burned down into carbon and oxygen rich cores not much larger than the Earth (but far more massive). John Timmer, Ars Technica, "White dwarf star covering itself with the atmosphere of a hot Neptune," 5 Dec. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'red giant.' 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 red giant

1929, in the meaning defined above

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Time Traveler for red giant Time Traveler

The first known use of red giant was in 1929

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Last Updated

11 Feb 2021

Cite this Entry

“Red giant.” Dictionary, Merriam-Webster, Accessed 8 Mar. 2021.

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More Definitions for red giant

red giant


English Language Learners Definition of red giant

astronomy : a very large star that has a reddish color

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