a site on a cell that, upon interaction with epinephrine or norepinephrine, controls vasoconstriction, intestinal relaxation, pupil dilation, and other physiological processes. Also,al'pha-re•cep"tor.Also called alpha-adrenergic receptor. Cf. beta receptor.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.