A violent storm, often of vast extent, characterized by high winds rotating about a calm center of low atmospheric pressure. This center moves onward, often with a velocity of twenty or thirty miles an hour.
- Meteorology An atmospheric system characterized by the rapid inward circulation of air masses about a low-pressure center, usually accompanied by stormy, often destructive weather. Cyclones circulate counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere.
- Meteorology A violent tropical storm, especially one originating in the southwestern Pacific Ocean or Indian Ocean.
- A violent rotating windstorm.
- Any of various devices using centrifugal force to separate materials.