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true rib

noun Anatomy.
  1. one member of the first seven pairs of ribs that are attached in humans to the sternum by costal cartilages.

Origin of true rib

First recorded in 1735–45
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for true rib

true rib

noun
  1. any of the upper seven pairs of ribs in man
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
true rib in Medicine

true rib

n.
  1. Any of the seven upper pairs of ribs attached to the sternum by costal cartilage.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.