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M star

noun

Definition of M star 

: a red star characterized primarily by a surface temperature of 3,000 kelvins or less

— called also Type M star

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First Known Use of M star

1927, in the meaning defined above

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Dictionary Entries near M star

msngr

MSS

MST

M star

MsTh1

MsTh2

mstr

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The first known use of M star was in 1927

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