cop (v.)
1704, northern British dialect, "to seize, to catch," perhaps ultimately from Middle French caper "seize, to take," from Latin capere "to take" (see capable); or from Dutch kapen "to take," from Old Frisian capia "to buy," which is related to Old English ceapian (see cheap). Related: Copped; copping.
cop (n.)
"policeman," 1859, abbreviation of earlier copper (n.2), 1846, from cop (v.).