To diminish, reduce, or make smaller; to lessen the extent, quality, or status of something.
From dis- (prefix meaning 'reduce' or 'reverse') + parish (from Old French paroisse, meaning 'district'). The verb evolved from a noun meaning administrative or church district, later generalized to mean 'reduce territory or extent'.
This is such an archaic word that even most historical scholars have forgotten it—it survives mainly in 17th-century legal documents describing the reduction of parish lands or administrative boundaries!
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