in petto[ēn pet′tō̂]
in petto 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.
secretly; not revealed: said of cardinals appointed by the pope but not named in consistory
Origin: Italian in the breast
in petto definition by American Heritage Dictionary
adverb & adj. Roman Catholic Church
In secret or private. Used of appointments of cardinals by the pope undisclosed in consistory.
Origin: Italian : in, in + petto, breast.