This noun appears in Acts 26:24 when Festus interrupts Paul's defense before Agrippa, shouting that Paul's great learning is driving him mad. The word can denote literal insanity or, as here, describes someone whose ideas seem so extreme they appear deranged. Classical Greek used the term both for clinical madness and for divine frenzy or enthusiasm. Festus cannot process Paul's account of resurrection and divine calling within his Roman rationalist framework, so he attributes it to derangement. Paul calmly responds that he speaks words of truth and soberness, not madness.