/ Dictionary / Index T tracheid: Meaning and Definition of Find definitions for: tra•che•id Pronunciation: (trā'kē-id), [key] — n. Bot. an elongated, tapering xylem cell having lignified, pitted, intact walls, adapted for conduction and support. Cf. vessel (def. 5). Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: tracheid (Thesaurus) tracheation tracheitis Related Content Daily Word Quiz: ravenous Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language