Webster's Revised Unabridged Dictionary · 1913

Energetic

Energetic , adjective

[Greek {not transcribed}, from {not transcribed} to work, be active, from {not transcribed} active. See Energy.]

1.
Having energy or energies; possessing a capacity for vigorous action or for exerting force; active.
A Being eternally energetic. — Grew
2.
Exhibiting energy; operating with force, vigor, and effect; forcible; powerful; efficacious; as, energetic measures; energetic laws.

Also: Energetical