plan·​et·​oid | \ ˈpla-nə-ˌtȯid How to pronounce planetoid (audio) \

Definition of planetoid

: a small body resembling a planet especially : asteroid

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Other Words from planetoid

planetoidal \ ˌpla-​nə-​ˈtȯi-​dᵊl How to pronounce planetoid (audio) \ adjective

Examples of planetoid in a Sentence

Recent Examples on the Web Ian Sample at The Guardian reports that the researchers didn’t press their eye to the telescope lens to find the little planetoids. Jason Daley, Smithsonian, "Researchers Discovered 20 Tiny New Moons Circling Saturn," 9 Oct. 2019 Without a star to call their own, the planetoids cool to a temperature that makes finding them a task for infrared eyes. National Geographic, "Black Hole at Galaxy's Heart Launches Planet-Size 'Spitballs'," 5 Jan. 2017 New to this version: the ability to drill from one side of a planetoid to the other. Chris Kohler, WIRED, "Top 10 Game Trailers From E3," 10 June 2009

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

1803, in the meaning defined above

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Time Traveler for planetoid

Time Traveler

The first known use of planetoid was in 1803

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Cite this Entry

“Planetoid.” Dictionary, Merriam-Webster, Accessed 1 Mar. 2021.

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