Nurse Ratched is a fictional character and the main antagonist of One Flew Over the Cuckoo's Nest, first featured in Ken Kesey's 1962 novel as well as the 1975 film adaptation. A cold, heartless tyrant, Nurse Ratched has become the stereotype of the nurse as a battleaxe. She has also become a popular metaphor for the corrupting influence of institutional power and authority in bureaucracies such as the psychiatric treatment center in which the novel is set.

One Flew Over the Cuckoo's Nest is a novel by Ken Kesey published in 1962. Set in an Oregon psychiatric hospital, the narrative serves as a study of institutional processes and the human mind, including a critique of psychiatry and a tribute to individualistic principles. It was adapted into the Broadway play One Flew Over the Cuckoo's Nest by Dale Wasserman in 1963. Bo Goldman adapted the novel into a 1975 film of the same name directed by Miloš Forman, which won five Academy Awards.