What is the nonfat part of the body termed?

The nonfat part of the body termed as lean body mass. Technically, it’s the amount of weight on the body which is considered as nonfat. Lean body mass is an important consideration as its weight must be relatively constant. So, if you’re aiming a body shape or weight especially if you’re an athlete, body builder, etc. your lean body mass should not change rather you burn or reduce your body fat percentage.