pro·​to·​sun | \ ¦prōtō+ \

Definition of protosun

: protostar especially : the gaseous cloud that underwent gravitational collapse to form the sun

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First Known Use of protosun

1949, in the meaning defined above

History and Etymology for protosun

prot- + sun entry 1

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The first known use of protosun was in 1949

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Cite this Entry

“Protosun.” Dictionary, Merriam-Webster, Accessed 22 Feb. 2020.

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