Pronunciation: (per"u-stôl'sis, -stal'-), [key]
—pl. -sesPronunciation: (-sēz). [key] Physiol.
the progressive wave of contraction and relaxation of a tubular muscular system, esp. the alimentary canal, by which the contents are forced through the system.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.