Berserk

Ber·serk

Berserk

n.
  1. One of a class of legendary heroes, who fought frenzied by intoxicating liquors, and naked, regardless of wounds. (Scand. Myth.)
  2. One who fights as if frenzied, like a Berserker.

Berserk

a.
  1. frenzied; crazed; usually in predicate position.