xiphoid process

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun The smallest and lowest of the three divisions of the human sternum, which is cartilaginous in early life but usually ossifies by adulthood.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun anatomy The cartilaginous extension of the lower sternum; the xiphisternum.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun smallest of the three parts of the breastbone; articulates with the corpus sternum and the seventh rib