/ Dictionary / Index H homovanillic acid: Meaning and Definition of Find definitions for: ho'mo•va•nil'lic ac'id Pronunciation: (hō'mō-vu-nil'ik, hom'ō-, hō"mō-, hom"ō-), [key] — Biochem. Biochem. the end product of dopamine metabolism, CHO, found in human urine. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. homotypic homozygosis Related Content Daily Word Quiz: dissonant Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language