1610s, "territory under the jurisdiction of a lord or officer," from French district (16c.), from Medieval Latin districtus "restraining of offenders, jurisdiction," then under the feudal system "area of jurisdiction," noun use of past participle of Latin distringere "hinder, detain" (see distress). Used vaguely of "any tract of land" from 1712. District attorney attested by 1789, American English.