/ Dictionary / Index M Mongolian idiocy: Meaning and Definition of Find definitions for: Mongo'lian id'iocy Pronunciation: [key] (often l.c.)(no longer in technical use) Down syndrome. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Mongolian hot pot Mongolian People's Republic Related Content Daily Word Quiz: placid Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language