/ Dictionary / Index D demyelination: Meaning and Definition of Find definitions for: de•my•e•li•na•tion Pronunciation: (dē"mī u-lu-nā'shun), [key] — n. loss of myelin from the nerve sheaths, as in multiple sclerosis. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: demyelination (Thesaurus) demyelinate demystify 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