What do you understand by weight?

Hint
Weight is used as the measure of mass in a body as measured in given gravity, try to revolve your answer around this definition.

Complete step by step answer
Weight is the force exerted by a body on the surface of a planet or the force exerted by the planet on the body.
This force is conservative in nature and is primarily caused by gravitational forces. Weight of a body is not constant but varies from planet to planet. It is mainly dependent on the gravitational pull of the object and is expressed as
 $\Rightarrow W = mg$
Where W is the weight of the body
M is the mass of the body considered
g is the field of (equal to the acceleration due to) gravity of Earth and it is dependent on the mass of the Earth varies from one heavenly body to another.

Note
Value of g is planet dependent and it is expressed as
 $\Rightarrow g = \dfrac{{Gm}}{{{r^2}}}$
Where G is the gravitational constant and its value is constant for all bodies
M is the mass of planet on whose we have to find g
R is the radius of planet considered
g changes with height, depth, due to shape of earth and due to rotation of earth.