Deranged means mentally disturbed in a way that makes someone behave irrationally or dangerously. When someone is described as deranged, their thinking has become so confused or distorted that they've lost touch with reality.

The word appears most often in news stories about criminals whose actions seem senseless or extreme. A deranged person might believe things that aren't true, make bizarre decisions that endanger themselves or others, or act in ways that seem completely disconnected from normal reasoning.

Derangement is like someone's thoughts have been knocked out of their proper arrangement. While we might jokingly call a plan or idea “deranged” when it seems wild or absurd, the word carries serious weight when describing an actual person. It suggests something has gone deeply wrong with how their mind processes the world, beyond simple confusion or poor judgment.

You might encounter this word in historical accounts, mystery novels, or news reports, but it's not a casual word to use about people, especially those you disagree with or whose choices you don't understand.