The word "berserk" describes a state of being frenzied, wildly angry, or irrationally enthusiastic. When someone is berserk, they are out of control, often acting in a violent or chaotic manner, as if they have lost their ability to think rationally. This term can also refer to intense emotions or actions that seem to be driven by an overwhelming force.
The term "berserk" has its roots in Old Norse. It comes from the word "berserkr," which refers to a type of warrior who fought with intense fury, often wearing bear skins ("ber" meaning bear and "serkr" meaning shirt). These warriors were said to enter a trance-like state of battle rage known as "berserkergang."