As an adjective, evil describes something very morally wrong, cruel, or harmful. As a noun, it refers to wickedness or harmful forces in general.
It comes from Old English 'yfel', meaning 'bad' or 'harmful', which covered both everyday badness and deep moral wrong. Over centuries, it narrowed to more serious moral and spiritual wrongs.
The word 'evil' once described ordinary bad luck as well as deep wickedness; only later did it become almost a villain label. That history shows how humans started separating simple mistakes from deliberate harm.
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