What is the general upper mass limit defining a low-mass star relative to the Sun?
Answer
Less than about eight times the mass of the Sun ($< 8 M_{\odot}$)
Astronomers generally classify a star as low-mass if its mass is less than about eight times the mass of the Sun ($M < 8 M_{\odot}$).

#Videos
Low Mass Stars: Crash Course Astronomy #29 - YouTube
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