1
general::
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.
Longman-Thesaurus