Vis /(?)/

Vis

Principle of vis viva: the principle that the difference between the aggregate work of the accelerating forces of a system and that of the retarding forces is equal to one half the vis viva accumulated or lost in the system while the work is being done.
Vis impressa: force exerted, as in moving a body, or changing the direction of its motion; impressed force.
Vis inertiae: The resistance of matter, as when a body at rest is set in motion, or a body in motion is brought to rest, or has its motion changed, either in direction or in velocity.
Vis mortua: dead force; force doing no active work, but only producing pressure.
Vis vitae: vital force.
Vis viva: living force; the force of a body moving against resistance, or doing work, in distinction from vis mortua, or dead force; the kinetic energy of a moving body; the capacity of a moving body to do work by reason of its being in motion. See Kinetic energy, in the Note under Energy. The term vis viva is not usually understood to include that part of the kinetic energy of the body which is due to the vibrations of its molecules.

A document or an indorsement made on a passport by the proper authorities of certain countries, denoting that the passport has been examined, and that the person who bears it is permitted to proceed on her journey. Same as visa; -- an older spelling now used less frequently than visa.

v. t.

imp. & p. p. Viséed; p. pr. & vb. n. Viséing