1. a state of mental disorder or insanity
Usage: formal or literary
2. the act or process of disturbing the normal order or arrangement of something

Examples

• The character's derangement became evident as his behavior grew increasingly erratic.
• Years of isolation contributed to his mental derangement.
• The derangement of the files made it impossible to locate the documents.
• The storm caused a complete derangement of the garden's carefully planned layout.
• Doctors diagnosed him with a severe derangement of the mind.
• The derangement of the schedule disrupted the entire project timeline.