energy

n. power; vigor, liveliness, intensity; (Physics) capability of a physical system to carry out work

This article is about the physical quantity: for other uses of the word "energy", see Energy (disambiguation).* In physics and other sciences, energy (from the Greek ενεργός, energos, "active, working") is a scalar physical quantity that is a property of objects and systems of objects which is conserved by nature. Several different forms, such as kinetic, potential, thermal, electromagnetic, chemical, nuclear, and mass have been defined to explain all known natural phenomena.
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(n.)
Strength of expression; force of utterance; power to impress the mind and arouse the feelings; life; spirit; -- said of speech, language, words, style; as, a style full of energy.
  

(n.)
Power efficiently and forcibly exerted; vigorous or effectual operation; as, the energy of a magistrate.
  

(n.)
Internal or inherent power; capacity of acting, operating, or producing an effect, whether exerted or not; as, men possessing energies may suffer them to lie inactive.
  

(n.)
Capacity for performing work.
  

Energy [from Greek energeia possessing + ergon active power] In physics, energy is treated as a measurable quantity, without reference to its actual nature or source. It used to be considered as distinct from and correlative to either matter, inertia, or mass; but now the conception of mass or matter as distinct from energy has disappeared.
Science admits the existence of vast stores of latent energy in the atoms; and considering everything as a question of physical dynamics, it infers that an equivalent quantity of physical energy must have been expended in creating the atom. Energy or life is a fundamental attribute and function of the universe, which has its manifestations on all seven or ten planes of prakriti, appearing as centers of energy which radiate outwards from within. Also used to denote the female potency or sakti (SD 1:l36); aether too is mentioned as the quintessence of energy. Energy expended on the astral plane is far more productive of results than the same amount expended on the physical plane, according to occult dynamics.
Theosophy makes a distinction between force (or forces) and energy. The former is the name of active monadic essences, each one of which may be considered to be a living, intelligent, self-conscious force; and when this force is actively used, its power to do work or to produce effects is energy.

the capacity for doing work.