/ Dictionary / Index A ameloblast: Meaning and Definition of Find definitions for: am•e•lo•blast Pronunciation: (am'u-lō-blast"), [key] — n. Anat. one of a layer of enamel-secreting cells covering the dentin of a developing tooth. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: ameloblast (Thesaurus) amelioration amen Related Content Daily Word Quiz: diurnal Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language