/ Dictionary / Index T tylosis: Meaning and Definition of Find definitions for: ty•lo•sis Pronunciation: (tī-lō'sis), [key] — pl. -ses a bubblelike formation in the cavity of tracheids or vessels in the wood of trees, consisting of protoplasm intruded from adjacent parenchyma cells. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Tyll Eulenspiegel tymbal Related Content Daily Word Quiz: perspicacious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language