What is the term for the area where sound particles are sparser in a sound wave?

In a sound wave, the term referring to the area where sound particles are sparser is known as rarefaction. Sound travels in waves, which consist of alternating regions where particles are compressed together (compression) and regions where they are spread apart (rarefaction). During rarefaction, the distance between the particles increases, resulting in lower pressure in that region compared to those in the compression phase. This phenomenon is crucial for understanding how sound waves propagate through different mediums, as it highlights the changes in particle density that occur as the waves travel. Therefore, recognizing rarefaction is essential for grasping the fundamental behavior of sound waves in physics.