(n)a catecholamine secreted by the adrenal medulla in response to stress (trade name Adrenalin); stimulates autonomic nerve action, Syn.epinephrin, adrenaline, Adrenalin
n. A hormone (C8H11NO3) secreted by the adrenal medulla; it also serves as a neurotransmitter, released at synapses; called also noradrenaline. Chemically it is 2-amino-1-(3, 4-dihydroxyphenyl)ethanol. It is a precursor of epinephrine in the body. Syn. -- noradrenaline. [ WordNet 1.5 ]