Othello syndrome: The delusion of infidelity of a spouse or partner. The Othello syndrome affects males and, less often, females. It is characterized by recurrent accusations of infidelity, searches for evidence, repeated interrogation of the partner, tests of their partner's fidelity, and sometime stalking. The syndrome may appear by itself or in the course of paranoid schizophrenia, alcoholism, or cocaine addiction. As in Othello, the play by Shakespeare, the syndrome can be highly dangerous and result in disruption of a marriage, homicide and suicide.
The Othello syndrome was named by the English psychiatrist John Todd (1914-1987) in a paper he published with K. Dewhurst entitled "The Othello Syndrome: a study in the psychopathology of sexual jealousy" (Journal of Nervous and Mental Disorder, 1955, 122: 367). Todd was also the first to name the Alice in Wonderland syndrome.
The Othello syndrome is also known as delusional jealousy, erotic jealousy syndrome, morbid jealousy, Othello psychosis, or sexual jealousy.