velocity

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

• noun Rapidity or speed of motion; swiftness.
• noun Physics A vector quantity whose magnitude is a body's speed and whose direction is the body's direction of motion.
• noun The rate of speed of action or occurrence.
• noun The rate at which money changes hands in an economy.

from The Century Dictionary.

• noun Quickness of motion; speed in movement; swiftness; rapidity; celerity: used only (or chiefly) of inanimate objects. See def. 2.
• noun .2. In physics, rate of motion; the rate at which a body changes its position in space; the rate of change of position of a point per unit of time.
• noun In music, decided rapidity of tempo or pace, particularly in a bravura passage.
• noun The velocity at which the mode of flow of a liquid, in a pipe or channel, is modified by the setting up of eddy-motion and the consequent interruption of the stream lines.
• noun Same as critical velocity .
• noun The velocity of a given individual wave-length of light as opposed to the group velocity of a complex beam taken as a whole.

from the GNU version of the Collaborative International Dictionary of English.

• noun Quickness of motion; swiftness; speed; celerity; rapidity
• noun (Mech.) 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.
• noun See under Angular.
• noun the velocity of a moving body at starting; especially, the velocity of a projectile as it leaves the mouth of a firearm from which it is discharged.
• noun the velocity with which a body approaches or recedes from another body, whether both are moving or only one.
• noun velocity in which the same number of units of space are described in each successive unit of time.
• noun velocity in which the space described varies from instant to instant, either increasing or decreasing; -- in the former case called accelerated velocity, in the latter, retarded velocity; the acceleration or retardation itself being also either uniform or variable.
• noun See under Virtual.

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

• noun physics A vector quantity that denotes the rate of change of position with respect to time, or a speed with the directional component.
• noun Rapidity of motion.
• noun The rate of occurrence.
• noun economics The number of times that an average unit of currency is spent during a specific period of time.

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

• noun distance travelled per unit time