Vigor /(?)/

Vig·or

Vigor

n.
  1. Active strength or force of body or mind; capacity for exertion, physically, intellectually, or morally; force; energy.
    The vigor of this arm was never vain.
  2. Strength or force in animal or vegetable nature or action; as, a plant grows with vigor.
  3. Strength; efficacy; potency.
    But in the fruithful earth . . . His beams, unactive else, their vigor find.

Vigor

v. t.
  1. To invigorate. [Obs.]