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esophagogastric junction

[ĭ-sŏf′ə-gō-găs′trĭk]
n.
  1. The line at the cardiac orifice of the stomach where there is a transition from the stratified squamous epithelium of the esophagus to the simple columnar epithelium of the stomach.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.