Peristalsis

The process of wave-like muscle contractions of the alimentary tract that moves food along.peristalsis
(Science: gastroenterology, physiology) The wormlike movement by which the alimentary canal or other tubular organs provided with both longitudinal and circular muscle fibres propel their contents. It consists of a wave of contraction passing along the tube for variable distances.
Origin: Gr. Stalsis = contraction
The contraction and relaxation of muscle tissue which can allow movement of a substance in a given direction, for instance in the throat, which moves mucus up the throat and food down.