/ Dictionary / Index O orthotropic: Meaning and Definition of Find definitions for: or•tho•trop•ic Pronunciation: (ôr"thu-trop'ik, -trō'pik), [key] noting, pertaining to, or exhibiting a mode of vertical growth. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. ortho-toluidine orthotropism Related Content Daily Word Quiz: vertigo Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language