from
The Collaborative International Dictionary of English v.0.48
Cyclone \Cy"clone\ (s?"kl?n), n. [Gr.????? moving in a circle,
p. pr. of ?????, fr. ky`klos circle.]
1. (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.
[1913 Webster]
Note: The atmospheric disturbance usually accompanying a
cyclone, marked by an onward moving area of high
pressure, is called an anticyclone.
[1913 Webster]
2. (Meteor.) In general, a condition of the atmosphere
characterized by a central area of pressure much lower
than that of surrounding areas, and a system of winds
blowing inward and around (clockwise in the southern
hemisphere and counter-clockwise in the northern); --
called also a {low-area storm}. It is attended by high
temperature, moist air, abundant precipitation, and
clouded sky. The term includes the hurricane, typhoon, and
tropical storms; it should not be applied to the moderate
disturbances attending ordinary areas of low pressure nor
to tornadoes, waterspouts, or "twisters," in which the
vertical motion is more important than the horizontal.
[Webster 1913 Suppl.]
3. A tornado. See above, and {Tornado}. [Middle U. S.]
[Webster 1913 Suppl.] Cyclone cellar