Deranged means insane. You've probably read headlines about deranged murderers, but someone might also be called deranged for bizarre behavior like wearing a bathing suit while skiing. Crazed, insane, demented, unbalanced, and unhinged are all synonyms for deranged.

What does it mean by deranged?

English Language Learners Definition of deranged

: unable to think or act in a normal or logical way especially because of severe mental illness : crazy or insane. See the full definition for deranged in the English Language Learners Dictionary. More from Merriam-Webster on deranged.

What does the medical term deranged mean?

Medical Definition of derangement

1 : a disturbance of normal bodily functioning or operation derangements in the secretion of adaptive hormones— Hans Selye. 2 : mental illness.