What term is usually used interchangeably with weight, representing the quantity of inertia possessed by an object?

The term that is typically used interchangeably with weight, and signifies the quantity of inertia possessed by an object, is mass. In physics, mass is defined as a measure of the amount of matter in an object and is a scalar quantity. It quantifies how much inertia an object has, which refers to its resistance to changes in its state of motion.

Weight, on the other hand, is the force exerted by gravity on an object and is directly proportional to its mass. This relationship is often represented by the equation weight = mass × gravitational acceleration. Therefore, while weight is dependent on both mass and the gravitational force acting on it, mass itself is an intrinsic property of the object that remains constant regardless of location.

In contrast, density refers to mass per unit volume and is not synonymous with weight, volume measures the space an object occupies, and force is a vector quantity that represents interaction causing an object to change its velocity. Therefore, mass stands out as the correct answer in the context of the question.