The term DEBILITATE refers to the weakening of a person or thing, either physically or mentally. SAP (3 letters) is a verb meaning to SAP or drain away strength or vitality. EXHAUST (7 letters) is a verb meaning to tire out completely. CRIPPLE (7 letters) is a verb meaning to DISABLE or IMPAIR severely. INCAPACITATE (12 letters) is a verb meaning to deprive of strength or ability. EXTENUATE (9 letters) is a verb meaning to reduce in force or degree. UNDERMINE (9 letters) is a verb meaning to WEAKEN or damage gradually. FATIGUE (7 letters) is a verb meaning to tire out or EXHAUST. DEVITALIZE (10 letters) is a verb meaning to deprive of vitality or strength. WEAKEN (6 letters) is a verb meaning to make weak or weaker. ATTENUATE (9 letters) is a verb meaning to make thin or slender. DISABLE (7 letters) is a verb meaning to deprive of strength or power. ENERVATE (8 letters) is a verb meaning to reduce in strength or vitality. ENFEEBLE (8 letters) is a verb meaning to make weak or feeble. IMPAIR (6 letters) is a verb meaning to make worse or less effective. All of these words are related to the term DEBILITATE and refer to the weakening of a person or thing.