Cy″clone (s?″kl?n), n. [Gr.����� moving in a circle, p. pr. of �����, fr. κύκλοσ circle.] (Meteor.) 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.
☞ The atmospheric disturbance usually accompanying a cyclone, marked by an onward moving area of high pressure, is called an anticyclone.