derangement

/dɪˈreɪndʒmənt/
noun
  1. A state of mental illness or insanity; wild or crazy behavior.
    • The doctor diagnosed the patient with temporary derangement after the accident.
    • The novel describes the slow derangement of a man living alone in the wilderness.
    • His sudden derangement shocked everyone who knew him as a calm person.
Antonyms
What does "derangement" mean? | whatsthatwordmean | whatsthatwordmean