Medical Dictionary
serotonin
noun se·ro·to·nin \ˌsir-ə-ˈtō-nən, ˌser-\
Medical Definition of SEROTONIN
: a phenolic amine neurotransmitter C10H12N2O that is a powerful vasoconstrictor and is found especially in the brain, blood serum, and gastric mucous membrane of mammals—called also 5-HT, 5-hydroxytryptamine
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