Which term refers to the regular repetition of compression and rarefaction in sound waves?

The term that refers to the regular repetition of compression and rarefaction in sound waves is "Periodic." In the context of sound waves, periodicity describes the consistent pattern that occurs as the waves propagate through a medium. Each cycle of compression and rarefaction occurs at a regular interval, indicating that the sound waves are periodic in nature.

Understanding periodicity is crucial in the study of acoustics and sound as it relates to musical tones and how they are perceived. This regularity influences characteristics like pitch, tone quality, and rhythm in music.

While other terms like rhythm, frequency, and amplitude are associated with sound, they do not specifically describe the regular repetition aspect in the same way. Rhythm pertains to the timing and duration of sound events in music, frequency measures the number of cycles per second of a wave (which relates more to pitch rather than the repeated pattern itself), and amplitude refers to the loudness of the sound, defined by the strength of the wave. Thus, "Periodic" accurately captures the concept of repeating cycles within sound waves.