Word Study
vasodilator
CIDE DICTIONARY
vasodilator, a. [L. vas a vessel + dilator.].
Causing dilation or relaxation of the blood vessels; as, the vasodilator nerves, stimulation of which causes dilation of the blood vessels to which they go. These nerves are also called vaso-inhibitory , and vasohypotonic nerves, since their stimulation causes relaxation and rest. [1913 Webster]
vasodilator, n. [L. vas a vessel + dilator.].
A substance which causes dilation of blood vessels. [PJC]
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