Cavitation

n. creation of cavities (Medicine, Physics)

Cavitation is a general term used to describe the behavior of voids or bubbles in a liquid. Cavitation is usually divided into two classes of behavior: inertial (or transient) cavitation and non-inertial cavitation. Inertial cavitation is the process where a void or bubble in a liquid rapidly collapses, producing a shock wave. Such cavitation often occurs in pumps, propellers, impellers, and in the vascular tissues of plants. Non-inertial cavitation is the process where a bubble in a fluid is forced to oscillate in size or shape due to some form of energy input, such as an acoustic field. Such cavitation is often employed in ultrasonic cleaning baths and can also be observed in pumps, propellers etc.
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Cav·i·ta·tion n. The formation of cavities in a body tissue or an organ, especially those cavities that form in the lung as a result of tuberculosis. [more]Cavitation - Community and Resources

n. cavitation, creation of cavities (Medicine, Physics)

the rapid formation and collapse of bubbles in a liquid.