- : The rippling motion of muscles in the digestive tract. In the stomach, this motion mixes food with gastric juices, turning it into a thin liquid.
* * *The movement of the intestine or other tubular structure, characterized by waves of alternate circular contraction and relaxation of the tube by which the contents are propelled onward. SYN: vermicular movement. [peri- + G. stalsis, constriction]- mass p. forcible peristaltic movements of short duration, occurring only three or four times a day, which move the contents of the large intestine from one division to the next, as from the ascending to the transverse colon. SYN: mass movement.- reversed p. a wave of intestinal contraction in a direction the reverse of normal, by which the contents of the intestine are forced backward. SYN: antiperistalsis.
* * *peri·stal·sis .per-ə-'stȯl-səs, -'stäl-, -'stal- n, pl -stal·ses -.sēz successive waves of involuntary contraction passing along the walls of a hollow muscular structure (as the esophagus or intestine) and forcing the contents onward compare SEGMENTATION (2)
* * *n.a wavelike movement that progresses along some of the hollow tubes of the body. It occurs involuntarily and is characteristic of tubes that possess circular and longitudinal muscles, such as the intestine. It is induced by distension of the walls of the tube. Immediately behind the distension the circular muscle contracts. In front of the distension the circular muscle relaxes and the longitudinal muscle contracts, which pushes the contents of the tube forward.• peristaltic adj.
* * *peri·stal·sis (per″ĭ-stawlґsis) [peri- + Gr. stalsis contraction] the movement by which the alimentary canal and other tubular organs that have both longitudinal and circular muscle fibers propel their contents; it consists of a wave of contraction passing along the tube for variable distances. peristaltic adj
Medical dictionary. 2011.