asteroid

noun
as·​ter·​oid | \ ˈa-stə-ˌrȯid How to pronounce asteroid (audio) \

Definition of asteroid

 (Entry 1 of 2)

1 : any of the small rocky celestial bodies found especially between the orbits of Mars and Jupiter
2 : starfish

asteroid

adjective

Definition of asteroid (Entry 2 of 2)

1 : resembling a star asteroid bodies in sporotrichosis
2 : of or resembling a starfish

Other Words from asteroid

Noun

asteroidal \ ˌa-​stə-​ˈrȯi-​dᵊl How to pronounce asteroid (audio) \ adjective

Examples of asteroid in a Sentence

Noun Most asteroids are found between Mars and Jupiter.
Recent Examples on the Web: Noun Samples from the asteroid Ryugu contained amino acids that are considered the precursors of life, a paper published Friday said, supporting a theory that solar-system rocks crashing into Earth helped jump-start primordial life-forms. Peter Landers, WSJ, 10 June 2022 That’s why having an early warning and asteroid monitoring system in place is vital. Joshua Hawkins, BGR, 27 Apr. 2022 After a delay in the flight of Boeing's Starliner mission in August 2021, the Atlas V rocket's first stage at Cape Canaveral that was to be used for that launch was repurposed for the Lucy asteroid mission. Eric Berger, Ars Technica, 15 Apr. 2022 SpaceX originally took the rap for the upcoming lunar litter after asteroid tracker Bill Gray identified the collision course in January. Marcia Dunn, chicagotribune.com, 2 Mar. 2022 SpaceX originally took the rap for the upcoming lunar litter after asteroid tracker Bill Gray identified the collision course in January. NBC News, 2 Mar. 2022 SpaceX originally took the rap for the upcoming lunar litter after asteroid tracker Bill Gray identified the collision course in January. Fox News, 2 Mar. 2022 SpaceX originally took the rap for the upcoming lunar litter after asteroid tracker Bill Gray identified the collision course in January. Marcia Dunn, The Christian Science Monitor, 2 Mar. 2022 SpaceX originally took the rap for the upcoming lunar litter after asteroid tracker Bill Gray identified the collision course in January. Marcia Dunn, Anchorage Daily News, 2 Mar. 2022 Recent Examples on the Web: Adjective Japan's Hayabusa2 space mission dropped samples from the asteroid Ryugu to Earth in the Australian outback in December 2020. Natalie Neysa Alund, USA TODAY, 10 June 2022 This should give scientists a treasure trove of data to analyze from the asteroid Bennu. Joshua Hawkins, BGR, 28 Apr. 2022 Kaiju are part of the fauna of the parallel world, where everything developed differently, mainly because there was no dinosaur-extinguishing asteroid impact millions of years ago. Tom Shippey, WSJ, 13 May 2022 Most of the glassy impact spherules that first revealed the fingerprints of the asteroid impact to DePalma are preserved as clay as a result of geological processes over millions of years. Katie Hunt, CNN, 11 May 2022 First discovered in 1807 by astronomer Heinrich Wilhelm Olbers, the Hubble Space Telescope observed that Vesta is large enough to have its own craters from asteroid impacts. Manasee Wagh, Popular Mechanics, 26 Apr. 2022 However, meteorite studies suggest that radiant gems can also form upon asteroid impacts. Elizabeth Gamillo, Smithsonian Magazine, 29 Mar. 2022 Finding ways to stop asteroid impacts isn’t a new goal that NASA has undertaken. Joshua Hawkins, BGR, 23 Mar. 2022 For example, next year NASA’s OSIRIS-REx spacecraft is expected to bring back samples from the asteroid Bennu, and Glavin and his team plan to look for some of these types of molecules. Quanta Magazine, 8 Mar. 2022 See More

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

First Known Use of asteroid

Noun

1802, in the meaning defined at sense 1

Adjective

1824, in the meaning defined at sense 1

History and Etymology for asteroid

Noun

Greek asteroeidēs starlike, from aster-, astēr

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Time Traveler for asteroid

Time Traveler

The first known use of asteroid was in 1802

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Dictionary Entries Near asteroid

Asterococcus

asteroid

asteroid belt

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Statistics for asteroid

Last Updated

26 Jun 2022

Cite this Entry

“Asteroid.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/asteroid. Accessed 27 Jun. 2022.

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More Definitions for asteroid

asteroid

noun
as·​ter·​oid | \ ˈa-stə-ˌrȯid How to pronounce asteroid (audio) \

Kids Definition of asteroid

: one of thousands of rocky objects that move in orbits mostly between those of Mars and Jupiter and have diameters from a fraction of a mile to nearly 500 miles (800 kilometers)

asteroid

adjective
as·​ter·​oid | \ ˈas-tə-ˌrȯid How to pronounce asteroid (audio) \

Medical Definition of asteroid

: resembling a star

More from Merriam-Webster on asteroid

Nglish: Translation of asteroid for Spanish Speakers

Britannica English: Translation of asteroid for Arabic Speakers

Britannica.com: Encyclopedia article about asteroid

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