English word dementor comes from Latin mens (Intellect. Mind. Reasoning, judgement.), Latin demento (I bewitch. I delude. I make mad or crazy.)
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mens (Latin)
Intellect. Mind. Reasoning, judgement.
demento (Latin)
I bewitch. I delude. I make mad or crazy.
demens (Latin)
Out of one's mind or senses; mad, raving, foolish, insane, reckless.
dementor (English)
An evil and fearsome creature.