Coriolis force

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A pseudo force used mathematically to describe motion, as of aircraft or cloud formations, relative to a noninertial, uniformly rotating frame of reference such as the earth.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun A force exerted on a parcel of air (or any moving body) due to the rotation of the earth. This force causes a deflection of the body to the right in the northern hemisphere and to the left in the southern hemisphere.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun (physics) a force due to the earth's rotation; acts on a body in motion (airplane or projectile) in a rotating reference frame; in a rotating frame of reference Newton's second law of motion can be made to apply if in addition to the real forces acting on a body a Coriolis force and a centrifugal force are introduced