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mid-14c., "to examine, scrutinize, inspect," from over- + look (v.). Another Middle English sense was "to peer over the top of." These two literal senses have given rise to the two main modern meanings. Meaning "to look over or beyond and thus not see," via notion of "to choose to not notice" is first recorded 1520s. Seemingly contradictory sense of "to watch over officially, keep an eye on, superintend" is from 1530s. Related: Overlooked; overlooking. In Shekaspeare's day, overlooking also was a common term for "inflicting the evil eye on" (someone or something).