The nickname used in the literature of psychoanalysis to refer to an early patient of Sigmund Freud (1856–1939). The Rat Man was tormented by fantasies of rats gnawing at his father's anus and that of a woman to whom he was attracted. Freud's case study, published in 1909, entitled ‘Notes upon a Case of Obsessional Neurosis’ (Standard Edition, X, pp. 155–320), is a classic text on the psychoanalytic theory of obsessive-compulsive disorder. See also undoing.