A type of tropical atmospheric ‘disturbance’ characterized by masses of air rapidly circulating clockwise in the southern hemisphere, a low pressure center, usually accompanied by stormy, often destructive weather. Atmospheric system of low barometric pressure (depression ) accompanied by strong winds that rotate counter-clockwise in the northern hemisphere and clockwise in the southern hemisphere. Called ‘cyclone’ in the Indian ocean and southern Pacific, it is called ‘hurricane’ in the western Atlantic and eastern Pacific and ‘typhoon’ in the western Pacific.