What does maniac mean in Greek?

Maniac (μανιακός, maniakό̱s) comes from the Greek word mania (μανία, manía), which means "madness, frenzy, or rage." It is related to the verb mainesthai (μαίνεσθαι, maínesthe), which means "to be mad or insane." The ancient Greeks believed that mania was caused by the gods or by natural causes, such as a fever or head injury.