Vas`o*di*lat"or (?), a.[L. vas a vessel + dilator.] Physiol.
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.
© Webster 1913.