(n)any agent that causes a narrowing of an opening of a blood vessel: cold or stress or nicotine or epinephrine or norepinephrine or angiotensin or vasopressin or certain drugs; maintains or increases blood pressure, Syn.pressor, vasoconstrictive
The Collaborative International Dictionary of English (GCIDE) v.0.53Collaborative International Dictionary (GCIDE)
n. (Medicine, Physiology) A substance which causes constriction of the blood vessels. Such substances are used in medicine to raise abnormally low blood pressure. [ PJC ]
a. (Physiol.) Causing constriction of the blood vessels; as, the vasoconstrictor nerves, stimulation of which causes constriction of the blood vessels to which they go. These nerves are also called vasohypertonic. [ 1913 Webster ]