recto-

word-forming element meaning "pertaining to or involving the rectum," before vowels rect-, from comb. form of rectum.

Online Etymology Dictionary, © 2010 Douglas Harper

recto- in Medicine

recto-

pref.
  1. Rectum:rectoscope.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.