Green’s Dictionary of Slang

1. a pocket.

1895

Mirror of Life 3 Aug. 7/2: ‘Jemmy the Sweep,’ who after sharping an American out of £200 at skittles put the money in his behind ‘tag’ (pocket).

2. (UK/US black) a name.

1900		Wichita Times (WI) 1 Sept. 1/5: The best example of this [...] human monstrosity extant [...] now abides in ‘Nutmeg and wooden ham’ Connecticut [...] and his tag reads ‘Charles A. Ticker .
1924		D. Hammett ‘The Tenth Clew’ in Continental Op (1975) 28: ‘He’s with the Continental Detective Agency’ [...] That tag — clearly a warning for Smith’s benefit — brought me to my feet.
1933		Ersine Und. and Prison Sl.
1944		D. Runyon Runyon à la Carte 58: Your tag is now Johnny One-Eye.
1958		Mad mag. May–June 20: It’s only your tag that hangs me up.
1965		W. King ‘The Game’ in King Black Short Story Anthol. (1972) 303: Some stiff-ass farmer tossed me and my brothers a tag long time ago with a heap others doing same.
1990		W.D. Myers Mouse Rap 3: You can call me Mouse, ‘cause that’s my tag / I’m into it all, everything’s my bag.
2001		N. Barlay Hooky Gear 16: Everythin wha his dad hand on to him includin, for a laugh, the pawnbrokers tag of Uncle.
2008		R. Price Lush Life 229: Yolanda [...] punched in True Life; no one in the system popping up with that tag .

3. a vehicle number-plate.

1900		St Bernard Voice (Arabi, LA) 19 May 3/2: If any person shall use a vehicle [...] on the public roads without first obtaining [...] the tag or plate herein provided for .
1920		Wash. Times (DC) 17 Dec. 13/2: Any person without a 1921 tag after the new year is liable to arrest.
1934		E. Caldwell Tobacco Road (1958) 81: You can drive a new car anywhere in the State for seven days while you are waiting for the tags to come from Atlanta.
1969		D. Pendleton Executioner (1973) 86: A red sports car! [...] Out-of-state tags.
1974		Miami News (FL) 27 June 11/4: Tag agency personnel encourage motorists to buy their tags through the mail.
1987		(con. 1970s) J. Pistone Donnie Brasco (2006) 264: He had noticed that Rossi’s car had Pennsylvania tags.
1996		Anniston Star (AL) 19 May 13A/2: Antique tags may soon be collectors’ items.
2000		G. Pelecanos Shame the Devil 133: The tags were stolen locally. The vehicle was traced to an auction down South.
2009		Columbian-Progress (MS)16 July 4/2: Mississippi’s system of pricing car tags stinks.

4. (US prison) a letter smuggled out of prison.

1931

G. Milburn ‘Convicts’ Jargon’ in AS VI:6 441: tag, n. A letter smuggled out of prison.

5. (US) a parking ticket.

1934		T. Minehan Boy and Girl Tramps of America (1976) 185: He makes out a tag because Jimmy’s car is parked right next to a fire hydrant [...] I see the cop is going to put a tag on the car.
1955		L. Allen Hot Stove League 3: [H]e had to spell [his name] out three times for a Chicago traffic cop who was issuing him a tag.
1996		(con. mid-1960s) J. Lardner Crusader 66: ‘You are personally going to pay the tag you put on the chef’s Cadillac,’ the sergeant said.

6. (US Und.) an arrest warrant.

1934		R. Chandler ‘Finger Man’ in Pearls Are a Nuisance (1964) 93: Is there a tag out for me?
1938		R. Chandler ‘Red Wind’ Red Wind (1946) 35: Tag out for this kid?
1955		‘Blackie’ Audett Rap Sheet 140: There was no tag out for the car.
1989		J. Morton Lowspeak.

7. a car licence.

1943

W. Guthrie Bound for Glory (1969) 190: ‘Selling automobile licenses!’ Roy said. And Mama said, ‘Car tags.’.

8. a label commonly given to a person or thing.

1946		E. Wilson Pikes Peek or Bust 137: I’m always getting crackpot letters heckling me for calling my wife ‘my Beautiful Wife—the B.W’ [...] My wife, I think, dislikes the B.W. tag too.
1976		Daily Tel. 20 July 3/2: The Black Panther tag, probably coined by the press, was the worst of it .
2000		Indep. 27 Jan. 11: These ranges, costing about half as much as designer tags, will bear the M&S label.

9. the ‘signature’ used by a graffiti artist, spraying their name on walls, subway trains etc.

1980		N.Y. Times Mag. 19 Oct. 44/5: It is close to a decade since the advent in New York of graffiti tags, often simply newly minted nicknames or random combinations of letters .
1987		D. Hebdige Cut ’n’ Mix 141: Individual artists used magic markers and spray paint to scribble their ‘tags.’.
1997		Simon & Burns Corner (1998) 21: That meant mostly street fights and dotting brick walls and asphalt with Crenshaw Mafia tags.
1999		Indep. Rev. 9 Nov. 10: Tags in graffiti are all important – dating back to the Sixties in America when city teenagers competed with each other to get their names on walls and trains as often as possible.
2003		T. White Foxy-T 3: They got proper names them two init but everyone still call them by there tags what are everywhere.
2010		Arizona Dly Star (Tucson, AZ) 19 Dec. A5/1: The 200 blocks of East Eight Street had 357 tags cleaned up.

10. (US prison) a piece of information.

2004

N. Kelley ‘The Code’ in Brooklyn Noir 172: A tag quickly went down that Code wasn’t somebody you wanted to fuck with.