an amine, CHNO, that is an intermediate biochemical product in the synthesis of norepinephrine, epinephrine, and melanin, and is a neurotransmitter
See dopamine in American Heritage Dictionary 4
(dōˈpə-mēnˌ)
noun
A monoamine neurotransmitter formed in the brain by the decarboxylation of dopa and essential to the normal functioning of the central nervous system. A reduction in its concentration within the brain is associated with Parkinson's disease.