Answer:
Compressibility.
Step-by-step explanation:
The compressibility of a fluid can be defined as a measure of the change in volume (density) with respect to the amount of pressure applied to the fluid. Thus, as the pressure of a compressible fluid increases, both its viscosity and density increases.
Some examples of compressible fluids are vapors, gases, air etc.
Hence, compressibility is the property that describes the amount of volume that decreases when pressure is applied to a fluid.
Additionally, the compressibility of fluids plays a significant role in the field of science such as in aerodynamics, fluid mechanics, thermodynamics etc.