one member of the first seven pairs of ribs that are attached in humans to the sternum by costal cartilages.
any of the upper seven pairs of ribs in man
Collins English Dictionary - Complete & Unabridged 10th Edition
2009 © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009
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.