/ Dictionary / Index M motu proprio*: Meaning and Definition of Find definitions for: mo•tu pro•pri•o Pronunciation: (mō't prō'prē-ō"), [key] — Latin. Latin. of one's own accord: used of certain documents issued by the pope without counsel from others. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. mottramite Mo-tze Related Content Daily Word Quiz: soporific Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language