► mentally ill having an illness that affects your mind and your behaviour: · Many mentally ill people are treated in the community.· He was declared mentally ill and unfit to stand trial.
► crazy informal mentally ill: · I couldn’t think straight. I felt like I was going crazy (=becoming crazy).
► mad old-fashioned mentally ill. This word is now usually considered offensive, and is usually used in a different meaning, when you think that someone’s ideas are not sensible: · Swift himself went mad (=became mad) later in life.· a mad old woman
► insane [not before noun] old-fashioned having a serious and permanent mental illness: · She went insane after her two young sons were murdered.· a hospital for the criminally insane
► disturbed not behaving in a normal way because of mental or emotional problems, especially problems that are caused by bad experiences: · She teaches emotionally disturbed children.· Her experiences left her deeply disturbed.
► unstable having an emotional state that often changes very suddenly: · Her mother was mentally unstable.· He lived in a small Putney flat with his ageing Aunt Bunny, and his emotionally unstable sister, Nancy.· He was too unstable to be a leader.
► deranged behaving in a crazy or dangerous way, usually because of being mentally ill: · A deranged young woman entered the school and took the life of one young boy.
► psychopathic having a serious and permanent mental illness that causes violent or criminal behaviour: · The film is about a psychopathic killer.
► psychotic suffering from or caused by a serious mental illness that changes your character and makes you unable to behave in a normal way: · psychiatric services for chronic psychotic patients.· There is a tendency for psychotic illnesses to be inherited.
► neurotic relating to or suffering from a mental illness that makes you unreasonably worried of frightened: · His mother was neurotic and insecure.· She’s neurotic about her weight.· A bored or lonely horse may become so neurotic that it chases itself around in circles.