Green’s Dictionary of Slang

1. (also copped-out) compromised, defeated.

1983		S. King Christine 66: But that was a copout job.
2000		J. Hawes Dead Long Enough 21: You think that all these tossers over twenty-five have somehow chosen their copped-out lives.

2. evasive.

1976		A. Salkey Come Home, Malcolm Heartland 146: What sort of cop-out response is that, man!
2000		N. Barlay Crumple Zone 200: Wha’ever don’t answer nuffink. Wha’ever is a noncey cop-out word.