n. Short for police officers. Originated from the TV show Hawaii 5-0 which was a copp show in the 1970's. Hawaii is the 50th state, hence the nickname "5-0".
Pigs -- sometimes hair-trigger killers with screamin' amps, party lights and big guns (the bad kind of each) anywhere, but specifically on any of the Hawaiian Islands.
Generally: anyone, anywhere packin' a badge or talkin' to someone who does; Cops; LVPD on bicycles; LAPD; NYPD; Sheriff's Deputy; CHiPs; Highway Patrol; State Police; Texas Ranger; feds; U.S. Marshall; DEA; BATF; undercover detective; the man; gubbamint agent; revenuer; Dog the Bounty Hunter; Officer of the Court; DA, judge; meter maid; security guard; narc; snitch; CI.
Even more broadly: paranoid label for anyone out-of-place in the hood; a person (potential witness) suspected of surveillance; someone who trades their legal troubles for incriminating testimony against someone else.
"This is McGarrett, FIVE-O. You're dusted (busted).
Book'em Dan-O (or Book him, Danno)."
"The Feds are bastards. Even Captain Steve McGarrett of Five-O don't like 'em for their inept and abusive heavy-handed tactics."