/ Dictionary / Index M mottled enamel: Meaning and Definition of Find definitions for: mot'tled enam'el Pronunciation: [key] fluorosis (def. 2). Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. mottled motto Related Content Daily Word Quiz: impetuous Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language