| Noun | 1. | angiotensin - any of several vasoconstrictor substances (trade name Hypertensin) that cause narrowing of blood vesselsangiotensin I - a physiologically inactive form of angiotensin that is the precursor to angiotensin II vasoconstrictive, vasoconstrictor - 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 | |