What does "vigor" mean?

Vigor: Strength or force in animal or force in animal or vegetable nature or action; as, a plant grows with vigor.

Additional senses

  1. 2.Strength; efficacy; potency. But in the fruithful earth . . . His beams, unactive else, their vigor find. Milton. Note: Vigor and its derivatives commonly imply active strength, or the power of action and exertion, in distinction from passive strength, or strength to endure.
  2. 3.To invigorate. [Obs.] Feltham.

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