Breadcrumb Home > Dictionary > Index P preclinical: Meaning and Definition of Find definitions for: pre•clin•i•cal Pronunciation: (prē-klin'i-kul), [key] — adj. Med. of or pertaining to the period prior to the appearance of the symptoms. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: preclinical (Thesaurus) preclimax preclude ✖ Related Content Daily Word Quiz: nabob Analogy of the Day: Today’s Analogy Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language