Deprive of strength is a term that can be used to describe the weakening of an individual or object. ENFEEBLE (8 letters) means to make weak or feeble, UNNERVE (7 letters) means to make someone feel nervous or anxious, ENERVATE (8 letters) means to reduce the strength or vitality of something, DRAIN (5 letters) means to draw off a liquid or power gradually, and SAP (3 letters) means to weaken or exhaust. All of these words can be used to describe the process of depriving something of its strength.