Resolute or strenuously active.
Excellent, very good.
Exceedingly violent, severe, ferocious, cruel or savage.
Of exceptional quality, exhibiting boldness or chutzpah.
Threatening in appearance or demeanor.
Extremely; very.
Vigorous, energetic, or dynamic.
Producing a large amount of energy when reacting.
Having an energy greater than 100,000 electron volts.