Why is the ninth month called September?
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.
To plead guilty to a lesser charge than one might otherwise be tried for; escape a worse punishment by accepting a lesser one (1920s+ Police & underworld)
[origin uncertain; perhaps ultimately fr Latin capere ''seize,'' by way of French; police officer sense a shortening of copper; second sense ''seize, catch'' attested by 1704]