- any of various substances that interfere with the action of the beta receptors: used primarily to reduce the heart rate or force in the prevention, management, or treatment of angina, hypertension, or arrythmias.
- any of a class of drugs, such as propranolol, that inhibit the activity of the nerves that are stimulated by adrenaline; they therefore decrease the contraction and speed of the heart: used in the treatment of high blood pressure and angina pectoris
