What is the meaning of torture?

(DoD) As defined by Title 18, US Code, Section 2340, it is any act committed by a person acting under color of law specifically intended to inflict severe physical or mental pain or suffering (other than pain or suffering incidental to lawful sanctions) upon another person within his custody or physical control. "Severe mental pain or suffering" means the prolonged mental harm caused by or resulting from: (a) the intentional infliction or threatened infliction of severe physical pain or suffering; (b) the administration or application, or threatened administration or application, of mind-altering substances or other procedures calculated to disrupt profoundly the senses or personality; (c) the threat of imminent death; or (d) the threat that another person will imminently be subjected to death, severe physical pain or suffering, or the administration or application of mind-altering substances or other procedures calculated to disrupt profoundly the senses or personality.