Exact scientific definition of weight

[ScienceNostalgia101]

Despite my background in physics, I've never fully wrapped my head around what weight's supposed to be, other than "not the same thing as mass." It used to hardly even matter, but now I need to know for my students.

 

For instance, if an astronaut is in orbit around the Earth, and the centripetal force is provided by gravity at precisely the right magnitude for the astronaut to feel "weightless" in this non-inertial reference frame, said astronaut would experience "weightlessness," but force of gravity would not be zero. What would be zero is the normal force, as there is no need, until the astronaut encounters an object in spite of weightlessness, for a normal force. So is weight supposed to be the normal force, the gravitational force, or something else?

[Bufofrog]

Weight is the force of gravity.  The normal force is what keeps you from sinking to the center of the earth.

[MigL]

Weight is a force and rightfully expressed in Newtons.
Your weight is different on the moon because the force of gravity is different.
Your mass, however, is the same.

[swansont]

10 hours ago, ScienceNostalgia101 said:

Despite my background in physics, I've never fully wrapped my head around what weight's supposed to be, other than "not the same thing as mass." It used to hardly even matter, but now I need to know for my students.

 

For instance, if an astronaut is in orbit around the Earth, and the centripetal force is provided by gravity at precisely the right magnitude for the astronaut to feel "weightless" in this non-inertial reference frame, said astronaut would experience "weightlessness," but force of gravity would not be zero. What would be zero is the normal force, as there is no need, until the astronaut encounters an object in spite of weightlessness, for a normal force. So is weight supposed to be the normal force, the gravitational force, or something else?

What we perceive as weight is the force exerted on you by a scale when measuring your weight. Whatever force you feel to make you remain at rest in your reference frame (including an accelerating frame)

Your weight is the gravitational force, but your perceived weight doesn’t have to be the same.