/ Dictionary / Index S seropositive: Meaning and Definition of Find definitions for: se•ro•pos•i•tive Pronunciation: (sēr"ō-poz'i-tiv), [key] — adj. Med. showing a significant level of serum antibodies, or other immunologic marker in the serum, indicating previous exposure to the infectious agent being tested. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. seronegative seroreaction Related Content Daily Word Quiz: paradox Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language