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visceral swallow

n.
  1. An immature swallowing pattern, as of infants, marked by a thrust of the tongue and resembling the peristaltic, wavelike, muscular contractions observed in the gut.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.