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anal canal

noun
  1. the terminal part of the rectum forming the passage to the anus
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
anal canal in Medicine

anal canal

n.
  1. The terminal portion of the alimentary canal, extending from the pelvic diaphragm to the anal orifice.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.