energy

/ˈɛnədʒi/

noun

noun: energy

1. 1.

   the strength and vitality required for sustained physical or mental activity.

   "changes in the levels of vitamins can affect energy and well-being"

   synonyms:vitality, vigour, life, liveliness,  animation, vivacity, spirit, spiritedness, fire,  passion, ardour, zeal, verve, enthusiasm,  zest, vibrancy, spark, sparkle, effervescence,  exuberance, buoyancy, perkiness,  sprightliness; More

   • a person's physical and mental powers.

     plural noun: energies

     "an alternative is to devote your energies to voluntary work"