To forget; to fail to remember; to have lost from memory (archaic or dialectal).
From dis- (negation) + remember (from Old French 'remembrer', from Latin 'rememorari', to recall). The dis- version was used in Early Modern English but 'forget' became the standard form.
Some Appalachian dialects still use 'disremember' in exactly the way Shakespeare would have—it's a living fossil of Early Modern English preserved in isolated communities where older language forms survive.
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