Wiktionary
cop-killer
n. (context US informal English) a Teflon coated bullet
Usage examples of "cop-killer".
He flipped pages, saw that Audrey had circled listings for guest cottages offering newlywed rates and tried to picture an on-the-lam cop-killer and a thirty-seven-year-old ex-stripper basking in the South American sun.
He made a big last try at the two of them buying their way out of the country with a nationwide cop-killer APB on his head.
Rhyme hadn’t had any contact with Polling over the past few years—not since the cop-killer case in which Rhyme had been hurt.