to make someone insane or to cause mental deterioration; to drive mad.
From Latin 'dementare' (de- + mens, mind), meaning to deprive of mind. First appears in English in the 17th century as a verb form.
Unlike modern 'dementia' which describes a condition, 'dement' is an active verb — it's about the process of losing one's mind, suggesting the mind as something that can be taken or lost.
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