/ Dictionary / Index P precipitinogen: Meaning and Definition of Find definitions for: pre•cip•i•tin•o•gen Pronunciation: (pri-sip"i-tin'u-jun, -jen"), [key] — n. an antigen that stimulates precipitin production or that reacts with antibody in an immunoprecipitation reaction. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. precipitin precipitous Related Content Daily Word Quiz: opulent Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language