velocity

n. speed; rate of change of the position of a moving body in relation to its speed and direction of travel

In physics, velocity is defined as the rate of change of position. It is a vector physical quantity, both speed and direction are required to define it. In the SI (metric) system, it is measured in meters per second (m/s). The scalar absolute value (magnitude) of velocity is speed. For example, "5 metres per second" is a speed and not a vector, whereas "5 metres per second east" is a vector. The average velocity (v) of an object moving through a displacement in a straight line during a time interval is described by the formula:
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(n.)
Rate of motion; the relation of motion to time, measured by the number of units of space passed over by a moving body or point in a unit of time, usually the number of feet passed over in a second. See the Note under Speed.
  

(n.)
Quickness of motion; swiftness; speed; celerity; rapidity; as, the velocity of wind; the velocity of a planet or comet in its orbit or course; the velocity of a cannon ball; the velocity of light.
  

The number of times which a dollar is spent, or turns over, in a specific period of time. Velocity affects the amount of economic activity generated by a given money supply.