To make dead or to kill; an archaic or obsolete term meaning to deprive of life.
From Middle English 'be-' (prefix meaning to make or to cover) + 'dead' (lifeless). This verb formation was productive in Middle English but fell out of use.
This verb is essentially extinct in modern English, but it shows how flexibly Middle English could create new verbs by adding 'be-' to adjectives—a pattern we've almost completely abandoned.
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