noun, noun which may take the genitive case particle 'no'
lunatic; madman; insane person
Refers to a person who is mentally deranged or acts in a wildly irrational way. Can be used literally or figuratively.
He kept screaming like a madman.
The lunatic was confined to a hospital.
The people around him treated him like a madman.
He kept laughing like a lunatic.
精神異常者 is a clinical, formal term for someone with a mental disorder, while 狂人 is a plainer literary word for a madman.
狂人 is an old-fashioned, formal word for a madman, while サイコ is modern slang used casually, often as a mild insult or joke.
常人 means an ordinary, sane person, the opposite of 狂人, a madman.
狂気 is the abstract state of madness itself, while 狂人 is the person who is mad; learners often mix up which one refers to the state versus the person.
狂人 is counted with 人, the standard counter for people.
Compound of 狂 (kyō, 'mad, insane') and 人 (jin, 'person').