ˌsirəˈtōnə̇n, -tän- noun
( -s )
Etymology: sero- + ton ic + -in; from its constrictive effect
: a crystalline phenolic amine HOC 8 H 5 NCH 2 CH 2 NH 2 derived from indole that is a powerful vasoconstrictor, that occurs especially in the blood serum and gastric mucosa of mammals, in small amounts in the brain, and in the secretions of various amphibians and that is formed in animal tissues from tryptophan — called also 5-hydroxytryptamine