/ Dictionary / Index M monoamine: Meaning and Definition of Find definitions for: mon•o•a•mine Pronunciation: (mon"ō-u-mēn', -am'in), [key] — n. Biochem. any of various biogenic amine neurotransmitters having a single amino group, as dopamine, epinephrine, and norepinephrine. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: monoamine (Thesaurus) monoalphabetic substitution monoamine oxidase Related Content Daily Word Quiz: secular Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language