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floating rib

noun Anatomy.
  1. one member of the two lowest pairs of ribs, which are attached neither to the sternum nor to the cartilages of other ribs.

Origin of floating rib

First recorded in 1825–35
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for floating rib

floating rib

noun
  1. any rib of the lower two pairs of ribs in man, which are not attached to the breastbone
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
floating rib in Medicine

floating rib

n.
  1. Any of the two lowest pairs of ribs with no anterior attachment to the sternum.vertebral rib
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.