What is the term for a measure of the force of gravity on an object?

The term that describes the measure of the force of gravity acting on an object is weight. Weight is defined as the gravitational force exerted on an object by the Earth (or another celestial body). It is directly proportional to mass, which is the amount of matter in an object, but it specifically accounts for the effect of gravity.

Weight is expressed in newtons (N) in the International System of Units (SI), where one newton is defined as the force required to accelerate a one-kilogram mass at a rate of one meter per second squared. Importantly, an object's weight can change depending on its location (for example, an object weighs less on the Moon than on Earth due to the weaker gravitational pull).

In contrast, mass remains constant regardless of location. Density refers to the mass per unit volume of a substance, while volume measures the amount of space an object occupies. Therefore, weight is distinctly linked to gravity's effect on mass, making it the correct answer in this context.