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late 14c., "pertaining to a parish," from Anglo-French parochiel (late 13c.), from Old French parochial, from Late Latin parochialis "of a parish" (c.600), from parochia (see parish).
Figurative sense, "limited, narrow," as if confined to a small region, is from 1856 (also see parochialism). Parochial school is attested from 1755.