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

Definition of planetoid

: a small body resembling a planet especially : asteroid

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 That said, 2001 FO32's path will present astronomers with a rare opportunity to closely observe the planetoid because 1.25 million miles is still relatively close in astronomical terms. Julia Musto, Fox News, 13 Mar. 2021 Samples were first found in a meteorite (believed to be remains of a fragmented planetoid) that fell from space in 1879, but only in 2014 described as a distinct mineral. David Bressan, Forbes, 4 Mar. 2021 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, 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, 5 Jan. 2017 New to this version: the ability to drill from one side of a planetoid to the other. Chris Kohler, WIRED, 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.

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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Dictionary Entries Near planetoid

planetesimal hypothesis



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Cite this Entry

“Planetoid.” Dictionary, Merriam-Webster, Accessed 29 Jun. 2022.

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