Green’s Dictionary of Slang

1. a CID officer, a detective, a police officer.

1904		Daily Chronicle 17 Sept. 6/6: We had better slide; he looks like a ‘busy’.
1926		Nottingham Eve. Post 6 Sept. 4/3: [The] officers arrested Bottom. In his possession were pieces of paper [...] ‘Sergeant, 5s.; “bizzi” 5s.; three “flatties” 7s6d; “private flatty 2s 6d”.’ ‘Bizzi’ was a slang term for detective, ‘flatty’ for a constable and ‘private flatty’ for a plain clothesman.
1926		Eve. Herald (Dublin) 8 Sept. 6/1: It was intriguing to hear on authority of counsel [...] in a case at Chichester, that a ‘bizzi’ is racecourse slang for a detective.
1927		E. Wallace Squeaker (1950) 10: There never was a ‘busy’ that gave away a ‘squeaker’.
1938		G. Kersh Night and the City 241: The bloody street’s alive with busies.
1941		V. Davis Phenomena in Crime 78: Don’t come here if there’s a busy on your wheel!
1952		M. Allingham Tiger in the Smoke (1978) 81: ‘Who is he? A busy?’ ‘Busy! P’lice!’ Tiddy Doll spat.
1957		G. Kersh Fowlers End (2001) 235: By sheer chance, the busies got ’ere just when the trousis went bang.
1973		(con. mid-1960s) J. Patrick Glasgow Gang Observed 125: The local ‘busies,’ with whom the boys had most contact, had all been given nicknames.
1980		J. McClure Spike Island (1981) 28: ‘Jesus, look at the busies!’ Police officers are appearing from nowhere.
1989		(con. 1950s–60s) in G. Tremlett Little Legs 193: busybodies police.
1989		J. Morton Lowspeak 26: Bizzie – a police officer.
1998		K. Sampson Awaydays 12: An over-friendly Busy comes over to make our acquaintance.
1999		Observer 10 Jan. 14: Can’t we do anything to help him? What bizzies can we get to?
2000		N. Griffiths Grits 467: Now shut the fuck up, ere’s the busies.
2007		N. ‘Razor’ Smith Raiders 271: The desk clerk [...] told him that the bizzies were on their way up.
2015		I. Welsh Decent Ride 77: Jist tell ays if ye are [going to commit suicide], so ah kin gie the bizzies some story.
2019		M. Herron Joe Country [ebook] ‘[I]f I’d done half what he got up to I’d pretend to go doolally too, in case the busies turned up with a charge sheet’.

2. attrib. use of sense 1.

2001

K. Sampson Outlaws (ms.) 50: There’s a bizzy station just up from here.