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c.1400, instruccioun, "action or process of teaching," from Old French instruccion (14c.), from Latin instructionem (nominative instructio) "building, arrangement, teaching," from past participle stem of instruere "arrange, inform, teach," from in- "on" (see in- (2)) + struere "to pile, build" (see structure (n.)). Meaning "an authoritative direction telling someone what to do; a document giving such directions," is early 15c. Related: Instructions.