hamstring(noun, verb) noun1. one of the tendons at the back of the kneeDefinition categories: body, sinew, tendon verb1. make ineffective or powerless- The teachers were hamstrung by the overly rigid schedulesDefinition categories: emotion, bedevil, crucify, dun, frustrate, rag, torment2. cripple by cutting the hamstringDefinition categories: body, cripple, lame