lusus naturae[lo̵̅o̅′səs nə to̵or′ē]
lusus naturae definition by Webster's New World
Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio. Used by arrangement with John Wiley & Sons, Inc.
a sport of nature; freak of nature
Origin: Classical Latin
lusus naturae - Medical Definition
A conspicuous congenital abnormality.