¦ ̷ ̷ ̷ ̷ ̷ ̷ ¦ ̷ ̷ ̷ ̷ noun
: any of a group of receptors that are postulated to exist on cell surfaces of some effector organs and of tissues innervated by the sympathetic nervous system in order to explain the specificity of certain adrenergic agents in activating or blocking only some sympathetic activities (as vasodilation, increase in muscular contraction and beat of the heart, and relaxation of smooth muscle in the bronchi and intestine) — compare alpha-receptor herein