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protosun

noun
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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