a star that is cooler on its surface, smaller, and of fainter luminosity than the sun
red dwarf in American English
noun
Astronomy
any of the faint reddish stars having diameters about half that of the sun and low surface temperatures, about 2000–3000 K; a main sequence star of spectral type M
Word origin
[1915–20]This word is first recorded in the period 1915–20. Other words that entered Englishat around the same time include: conditioning, costar, decoder, stockpile, takeout