What term describes the measurement of the amount of matter in an object?

The term that describes the measurement of the amount of matter in an object is mass. Mass is a fundamental property of matter and is independent of the object's location or the force of gravity acting upon it. It quantifies the amount of substance contained in a given object and is typically measured in kilograms or grams.

In contrast, weight refers to the gravitational force acting on an object, which can change depending on the object's location (for example, weight would be different on the Moon compared to Earth). Volume is the measure of space that an object occupies, typically represented in liters or cubic centimeters. Density, on the other hand, is a ratio that relates mass to volume, often expressed in units like grams per cubic centimeter, indicating how much mass is contained in a given volume. Each of these concepts is important in the study of physics and chemistry, but the measurement of matter itself is specifically defined as mass.