An archaic or variant form meaning to impair or damage; to make worse or diminish.
From Old French empeirier, from em- (into) + peirier (to make worse). Related to impair and represents an older English form that was later standardized.
Old English had both 'impair' and 'empair,' but 'impair' won out—this is why English spelling can seem chaotic, because multiple competing forms existed in Middle English before standardization settled on winners.
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