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protoplanet

play
noun pro·to·plan·et \ˈprō-tō-ˌpla-nət\

Definition of protoplanet

  1. :  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

protoplanetary play \ˌprō-tō-ˈpla-nə-ˌter-ē\ adjective


1949

First Known Use of protoplanet

1949


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