/ Dictionary / Index M myatonia: Meaning and Definition of Find definitions for: my•a•to•ni•a Pronunciation: (mī"u-tō'nē-u), [key] — n. Pathol. deficient muscle tone. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. myasthenia gravis myatrophy Related Content Daily Word Quiz: philtrum Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language