Green’s Dictionary of Slang

(a) an experienced, but somewhat cunning individual, thus attrib.

1781		G. Parker View of Society II 92: Eager to raise the sum he wanted [...] he patiently beat the round of A.B. C.D. E.F. &c. and was for some days flattered by them all, until they found it impossible to extract any thing from him, who had been what is called An old Soldier.
1826		Bell’s Life in London 7 May 3/2: Richmond and Burton gave [...] some fine specimens of science [...] They are old soldiers and know how to ‘do the thing comfortably’.
1845		J. Lindridge Sixteen-String Jack 231: Do you think that all these smooth looks will have any effect upon an old soldier like me.
1861		(con. 1840s–50s) H. Mayhew London Labour and London Poor IV 43/1: He’s a regular old soldier, he is, sir.
1898		Regiment 11 June 165/1: He was an old soldier—in both senses of the phrase.
1901		People 7 April, 18, 2: An old soldier — both in the literal and metaphorical sense — down to every move on the board, suspicious and even touchy, he forms a genuine friend, ever ready to do his comrade a good turn [F&H].
1906		D. Stewart Vultures of the City in Illus. Police News 15 Dec. 12/1: He’s snide. Bill—too much the old soldier he is for me.
1915		C.E.W. Bean Anzac Book 134: [of a woman] ‘Love me and the world is yours,’ cooeed Sir Jasper into Muriel’s shell-like ear. But Muriel was an old soldier and knew better.
1929		A.J. Barr Let Tomorrow Come 72: Ol’ sojer, you fixin’ dis heah table or makin’ things peart?
1930		(con. 1914–18) Brophy & Partridge Songs and Sl. of the British Soldier 144: Old Soldier.—One grown old in sin.
1949		‘Josephine Tey’ Brat Farrar 239: ‘Of all the “old soldier” tricks to fall for!’ laughed Clint [...] ‘I ought to have my head examined’.
1959		A. Sillitoe ‘Loneliness of the Long-Distance Runner’ in Loneliness of the Long-Distance Runner (1960) 15: I grew up hearing the sound of ‘old soldiers’ who’d been over the top at Dartmoor, half killed at Lincoln, trapped in no-man’s land at Borstal.
1974		J. McNeil How Does Your Garden Grow Act III: Here, old soldier, lemme do it.
1999		Eble Campus Sl. Apr. 7: soldier – person with a strong will and perserverance.

(b) a simpleton, a naïve person.

1984

Partridge DSUE (8th edn) 826/2: mid–C.19–20; very ob.

(a) (orig. US) the stub of a cigar or cigarette; well-chewed tobacco.

1834		W.A. Caruthers Kentuckian in N.Y. I 12: We has plenty of the real Baltimores [...] as I knows very well, for I smokes the old sodgers what the gentlemen throws on the bar-room floor.
1845		T.J. Green Journal of the Texian Expedition 272: An ‘old soldier’ in this sense is not the absolute war-worn veteran [...] but a chew of tobacco, which has from time to time undergone mastication from friend to friend.
a.1877		Bartlett Dict. Americanisms (4th edn) 438: Ladies who swab our sidewalks, [...] Haul off old soldiers lying there at rest.
1880		Bulletin (Sydney) 25 Sept. 9/2: When Julius Caesar used to wear a ‘pinny’ and ‘wag it’ down to the Tiber Creek to smoke bits of cane and old ‘sojers’.
1882		‘Mark Twain’ ‘Answer to Correspondents’ in Celebrated Jumping Frog and Sketches 33: The most popular smoking tobacco [...] is composed of equal parts of tobacco stems, chopped straw, ‘old soldiers,’ fine shavings of oak-leaves.
1895		C. Crowe Aus. Sl. Dict. 54: Old Soldiers, cigar ends.

(b) an empty bottle.

1890–1904		Farmer & Henley Sl. and Its Analogues.
1994		C. Dexter Daughters of Cain (1995) 175: I remember a few weeks ago trying to get rid of an old soldier in a rubbish bin in Banbury Road.