Vorticity

In fluid dynamics, the vorticity is a pseudovector field that describes the local spinning motion of a fluid near some point (the tendency of something to rotate ), as would be seen by an observer located at that point and traveling along with the fluid. Conceptually, the vorticity could be determined by marking the particles of the fluid in a sma...
Found on http://en.wikipedia.org/wiki/Vorticity

Vorticity

A measure of the local rotation in a fluid flow. In weather analysis and forecasting, it usually refers to the vertical component of rotation (i.e., rotation about a vertical axis) and is used most often in reference to synoptic scale or mesoscale weather systems. By convention, positive values indicate cyclonic rotation.
Found on http://www.encyclo.co.uk/local/22268

vorticity

amount of vortical motion in a fluid
Found on http://phrontistery.info/v.html

Vorticity

The measurement of the rotation of a small air parcel. It has vorticity when the parcel spins as it
Found on http://www.superglossary.com/Glossary/Science/Weather/
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