Definition of flare star in English English dictionary
a red dwarf star in which luminosity can change several magnitudes in a few minutes
Star that varies in brightness repeatedly but sporadically, sometimes by more than one magnitude, within a few minutes. The cause is thought to be the eruption of flares like those observed on the Sun but much larger (see solar flare). Proxima Centauri, in Alpha Centauri, the closest star to the Sun, is a flare star