INVOLUNTARY

[adjective] [not gradable] - not done by choice; done unwillingly, or without the decision or intention of the person involvedA sharp tap on the leg beneath the knee usually causes an involuntary movement of the lower leg.They argued that legalising voluntary euthanasia (= letting people choose to die) would eventually lead to involuntary euthanasia.Facial expressions, body movements and posture provide involuntary clues to the emotional state of the person observed.There may have to be some involuntary redundancies.