Blue supergiant

Hot, luminous star with a spectral type of A9 or earlier

A blue supergiant (BSG) is a hot, luminous star, often referred to as an OB supergiant. They are usually considered to be those with luminosity class I and spectral class B9 or earlier, although sometimes A-class supergiants are also deemed blue supergiants.

This keyword could refer to multiple things. Here are some suggestions: