/ Dictionary / Index D dentin: Meaning and Definition of Find definitions for: den•tin Pronunciation: (den'tn, -tin), [key] — n. Dentistry. the hard, calcareous tissue, similar to but denser than bone, that forms the major portion of a tooth, surrounds the pulp cavity, and is situated beneath the enamel and cementum. See diag. under Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: dentin (Thesaurus) dentilingual dentirostral Related Content Daily Word Quiz: paradox Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language