Green’s Dictionary of Slang

1. a tumour.

1857

Globe (London) 19 Sept. 4/6: She was attacked with a swelling in the back which having turned into a ‘tombstone’ she was obliged to go into hospital to have it cut out.

2. a pawn ticket [the inscription ‘in memory of’ and the implication that once pawned, items are rarely possessed again].

1864, 1867, 1870		Hotten Sl. Dict. 259: Tombstone a pawn-ticket ? ‘In memory of’ &c., a well-known Slang expression with those Londoners who are in the habit of following ‘My Uncle.’.
1883		J. Greenwood Odd People in Odd Places 168: The [...] bag in which the ‘tombstones’ or pawn-tickets were deposited.
1891		Sporting Times 10 Jan. 3/1: His hundred guinea chronometer (for the ‘tombstone’ of which he had [...] given a fiver and a small bottle).
1909		J. Ware Passing Eng. of the Victorian Era.

3. a snaggle- or crooked tooth [resemblance].

1809		G. Andrewes Dict. Sl. and Cant.
1832		Egan Bk of Sports 160: What tho’ each tombstone they allow / To totter on their graves (gums — Egan’s gloss) from rattling blow.
1833		‘A Chaunt by Slapped-up Kate and Dubber Daff’ in Swell!!! or, Slap-Up Chaunter 47: Her tomb-stones are white as the one-in-ten wipe.
1848		Flash Dict. in Sinks of London Laid Open 128: Tombstones, teeth.
1855		Broadway Belle (NY) 17 Sept. n.p.: When she grins, her jaws look like a grave-yard well furnished with tomb-stones.
1863		Criminal Life (NY) 19 Dec. n.p.: You call yourself good-looking, but you had better take those two tombstones you call teeth, out of your mouth.
1901		Bulletin (Sydney) 14 Dec. 14/3: The [...] tombstone incisors were plentiful enough to suggest that fashions in dentistry are as arbitrary among the ‘naicest’ Percies as fashions in lies. Hitherto I had regarded those particular teeth as characteristic only of the Australian rabbit and the British ‘heir.’.
1897		Leicester Chron. 24 Apr. 12/2: Lord, lad, thy mouth needna shew me a grave an’ white tombstones o’ teeth.
1908		B. Fisher A. Mutt in Blackbeard Compilation (1977) 122: I wonder if it hurts much when they pull a tombstone.
1927		‘Jargon of the Und.’ in DN V 465: tombstone, A tooth. ‘The mouth is a graveyard.’.
1931		Irwin Amer. Tramp and Und. Sl. 189: Tombstones.– The teeth.
[1977		G. Melly Rum, Bum and Concertina (1978) 16: Teeth the size of important Victorian tombstone].

4. (US short-order) a poached egg.

1908

Commercial (Union City, TN) 22 May 5/1: An order of milk toast with a poached egg on top is [...] —‘Graveyard stew, tombstone on the top’.

5. (drugs) a capsule or pill of amphetamine.

2002

(con. 1981) W. Self Dorian 37: ‘What’s he on nowadays?’ [...] ‘Same as ever, five-mil Dexies in the day, tombstones or bombers if he’s out on the razzle.’.