It’s really just a sexy name, as far as I can tell, for a white dwarf that should have been obliterated in a supernova but remains partially alive. “Coma Star” doesn’t sound as good.
But I am surprised science discovered this and came up with the name before we got an episode of Doctor Who in which Peter Capaldi finds that the sun is in fact an actual giant zombie. Like, maybe it died from eating a rotten egg that was actually a moon of something.
Actual science below…