blue supergiant

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A supergiant star with surface temperature ranging from 10,000 to 40,000 kelvin (17,540° to 71,540° F), making the star appear blue-white.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun astronomy a very large, hot and luminous star; a large blue giant