/ Dictionary / Index O orthoselection: Meaning and Definition of Find definitions for: or•tho•se•lec•tion Pronunciation: (ôr"thō-si-lek'shun), [key] — n. Biol. orthogenesis (def. 1a). Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. orthoscopic orthosis Related Content Daily Word Quiz: immense Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language