/ Dictionary / Index D diagnostic: Meaning and Definition of Find definitions for: di•ag•nos•tic Pronunciation: (dī"ug-nos'tik), [key] — adj. of, pertaining to, or used in diagnosis. serving to identify or characterize; being a precise indication. —n. diagnosis (def. 1). a symptom or characteristic of value in diagnosis. a device or substance used for the analysis or detection of diseases or other medical conditions. a message output by a computer diagnosing an error in a computer program, computer system, or component device. a program or subroutine that produces such messages. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: diagnostic (Thesaurus) diagnosis diagnosticate Related Content Daily Word Quiz: hale Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language