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.
- The capacity for work or vigorous activity; vigor; power. See Synonyms at strength.
- Exertion of vigor or power: a project requiring a great deal of time and energy.
- Vitality and intensity of expression: a speech delivered with energy and emotion.
- Usable heat or power: Each year Americans consume a high percentage of the world's energy.
- A source of usable power, such as petroleum or coal.
- Physics The capacity of a physical system to do work.