Green’s Dictionary of Slang

1. an informant, a tell-tale.

1781		G. Parker View of Society II 83: snitchers are informers [...] If they should happen to refuse a brother sharper who is flash to the rig, and has been a by-stander, his whack, are instantly snitched upon; that is, the Snitcher follows the loser, and asks him what he will give him (the Snitcher) if he puts him in the way of recovering his money.
1796		Grose Classical Dict. of the Vulgar Tongue (3rd edn).
1811		Lex. Balatronicum.
1823		Egan Grose’s Classical Dict. of the Vulgar Tongue n.p.: To turn snitch, or snitcher; to turn informer.
1827		Lancaster Gaz. 29 Dec. 4/4: You are a snitcher — you peached — and I scorned you.
1853		Leics. Mercury 12 Mar. 3/6: He charged the sleeping partner of the ‘snitcher’ in Grant’s case with easing him of the money.
1864, 1867, 1870		Hotten Sl. Dict.
1889–90		Barrère & Leland Dict. of Sl., Jargon and Cant.
1895		Crowe Aus. Sl. Dict. 77: Snitchers, informers.
1898		Edinburgh Eve. News 22 Mar. 4/4: He is a regular snitcher.
1901		Argus (Melbourne) 20 Sept. 6/4: [If] he works in company he has an anxious time lest some of the stags or snitchers may chirp or cackle, squeak or whiddle, if hush stuff is not forthcoming or, to put it in plainer English, informers may speak unless they are paid for their silence.
1915		J. London Star Rover (1963) 9: He was a snitcher. He was a stool.
1928		M.C. Sharpe Chicago May (1929) 24: I was tipped off that poor Dal had been sent to his doom by a snitcher.
1936		J.T. Farrell World I Never Made 132: Gosh, how would he be able to make Bill believe that he hadn’t been a snitcher.
1949		Monteleone Criminal Sl. (rev. edn).
1958		Hughes & Bontemps Book of Negro Folklore 381: Way down in Polock town / Where de police an’ de snitchers, dey tore my playhouse down.
1967		in S. Harris Hellhole 242: They believe what they’ve seen in prison movies where ‘rats’ and ‘snitchers’ are always punished by horrible deaths.
1970		Manchester Guardian Weekly 2 May 16: You have burn artists (fraudulent dope peddlers), rip-offs (thieves), and snitchers (police spies).
1999		Observer 25 July 22: Daughter turns into snitcher [...] ready to tell all about her ‘phoney’ father.
2009		Times Rev. 30 Apr. 23/3: Someone needs to deal with these snitchers in the ’hood.

2. (UK und.) a hangman.

1791

H. Lemoine ‘Education’ in Attic Misc. 117: The dolman sounding, while the sheriff's nod, / Prepare the snitcher to dead hook the whack.

3. (Scot.) in pl., handcuffs, esp. strings used in place of handcuffs [? addition of SE snatch].

1860		Hotten Dict. of Modern Sl. etc. 221: In Scotland, snitchers signify handcuffs.
1864, 1867, 1870		Hotten Sl. Dict.
1869		Australiasian (Melbourne) 17 July 8/5: [A] handcuff is a snitcher .
1890–1904		Farmer & Henley Sl. and Its Analogues.
1914		N.Z. Truth 4 July 4/4: The stampeding ‘snitcher’ swinger easily became the observed of all observers.
1933		M. Marshall Tramp-Royal on the Toby 342: [footnote] There was issued to every man of the City police [...] a new pair of snitchers.
1949		Monteleone Criminal Sl. (rev. edn) 16: snitchers Handcuffs.

4. in weak use of sense 1, a contemptible person.

1888

Kipling ‘The Likes O’ Us’ in Civil & Military Gaz. 4 Feb. (1909) 101: Look a-here, you young snitcher.

5. a detective.

1923

J. Manchon Le Slang.

6. (US black, also snitch) a newspaper reporter or columnist, a writer.

1941		D. Burley N.Y. Amsterdam Star-News 21 June 13: The snitchers on the wrong side of the heavy drink had been laying don some righteous ink.
1944		D. Burley Orig. Hbk of Harlem Jive 18: I’ve been digging the snitches each and every bright and dim.
1944		‘Jiver’s Bible’ in D. Burley Orig. Hbk of Harlem Jive.