Definition of blue giant
astronomy
:a bluish star that has a high surface temperature and a diameter that is large relative to the sun
- Later, just a few thousand years before the supernova explosion, the red giant apparently lost some of its girth, forming a blue giant, which emits a faster, lower density wind.
- —Ron Cowen, Science News, 6 Mar. 1993
Note:
Blue giant is not a technical term and can be applied to a number of different types of stars, as long as they are large and hot enough to appear blue in the night sky.
— compare red giant 
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