SINCE 1828
protoplanet
noun
pro·to·plan·et
| \ ˈprō-tō-ˌpla-nət
\
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Definition of protoplanet
: a hypothetical whirling gaseous mass within a giant cloud of gas and dust that rotates around a sun and is believed to give rise to a planet
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Other Words from protoplanet
protoplanetary
\ ˌprō-tō-ˈpla-nə-ˌter-ē
\
adjective
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adjective
Examples of protoplanet in a Sentence
Recent Examples on the Web
The moon probably formed from another protoplanet smashing into the young Earth, and a runaway planet has long been the suspected culprit behind the odd tilt of Uranus. — John Wenz, Popular Mechanics, "We Might Finally Know What Smacked Uranus Sideways," 2 July 2018 The discoveries, and the new method used to make them, are a thrilling advancement of exoplanet sciences to include protoplanets still in the process of formation, which were previously hidden from view. — Jay Bennett, Popular Mechanics, "Three Newborn Planets Discovered Around an Infant Star," 13 June 2018 Fortunately, the study of protoplanets is just getting started. — Jay Bennett, Popular Mechanics, "Three Newborn Planets Discovered Around an Infant Star," 13 June 2018 Therefore, the meteorite diamonds reveal information about their parent protoplanet. — Doris Elin Salazar, Scientific American, "Diamonds in Meteorite May Come from a Lost Planet," 18 Apr. 2018 The diamonds themselves may have been larger until the protoplanet was destroyed. — John Wenz, Popular Mechanics, "Diamond-Encrusted Meteorite Could Be From a Lost Planet," 17 Apr. 2018 The diamond pieces inside the meteorite hold a compelling record of these protoplanets and their collisions, according to the study. — Doris Elin Salazar, Scientific American, "Diamonds in Meteorite May Come from a Lost Planet," 18 Apr. 2018 The protoplanet in question may have originated in the outer solar system and migrated inward to the inner solar system. — John Wenz, Popular Mechanics, "Diamond-Encrusted Meteorite Could Be From a Lost Planet," 17 Apr. 2018 As Sarah Gibbens at National Geographic reports, in the first 10 million years of our planetary family, swarms of protoplanets composed of rock, dust and gas likely pinballed around the sun. — Jason Daley, Smithsonian, "Diamonds Trapped in Strange Meteorite Came From Solar System’s Earliest Planets," 19 Apr. 2018These example sentences are selected automatically from various online news sources to reflect current usage of the word 'protoplanet.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
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