energy

 
Pronunciation: /ˈɛnədʒi/

noun (plural energies)

[mass noun]
  • 1the strength and vitality required for sustained physical or mental activity: changes in the levels of vitamins can affect energy and well-being
  • (energies) a person’s physical and mental powers: an alternative is to devote your energies to voluntary work
  • 2power derived from the utilization of physical or chemical resources, especially to provide light and heat or to work machines: nuclear energy
  • 3 Physics the property of matter and radiation which is manifest as a capacity to perform work (such as causing motion or the interaction of molecules): a collision in which no energy is transferred

Origin:

mid 16th century (denoting force or vigour of expression): from French énergie, or via late Latin from Greek energeia, from en- 'in, within' + ergon 'work'