Freebase(0.00 / 0 votes)Rate this definition: Diltiazem. Diltiazem is a nondihydropyridine member of the class of drugs known as calcium channel blockers, used in the treatment of hypertension, angina pectoris, and some types of arrhythmia. It is also an effective preventive medication for migraine. It is a class 3 antianginal drug, and a class IV antiarrhythmic.
Rigid definition, stiff or unyielding; not pliant or flexible; hard: a rigid strip of metal. See more.
Definition of pendulum 1: a body suspended from a fixed point so as to swing freely to and fro under the action of gravity and commonly used to regulate movements (as of clockwork) 2: something (such as a state of affairs) that alternates between opposites