Green’s Dictionary of Slang

1. (S.Afr.) a generic name for any Hindu, esp. Indian people living in South Africa [abbr. SE ramsammy].

1886		Yule & Burnell Hobson-Jobson (1996).
1905		J.G. Cruickshank Negro Humour 13: Sammy resumes his seat growling ‘Na-guh! son-oer—’. [Ibid.] 78: Sammy.—A name applied here generally to East Indians.
1968		K. McMagh Dinner of Herbs 18: The Indian males were known as Sammy.

2. (US) a US soldier during WWI [Uncle Sam n.¹ ].

1918		Wash. Times (DC) 6 Feb. 3/5: [headline] Sammies Restlessly Await Heavy Attack.
1918		letter in M. Baldwin Canteening Overseas (1920) 94: The Sammies are right in the ‘thick of it’ now.
1918		H.V. O’Brien diary 14 May in Wine, Women and War (1926) 90: Home papers still referring to ‘Sammies.’ How the boys hate that word!
1918		D.G. Rowse Doughboy Dope 105: Anyone who has seen a considerable number together knows why they are Yanks, and nothing else, especially not ‘Sammies’.
1918		Cairns Post 12 Mar. 7/4: The British Recruiting Mission have prepared a glossary of trench slang [...] The British Recruiting Mission have prepared a glossary of trench slang [...] Sammies. - This name has been widely adopted by the British troops as a name for their American comades-in-arms. lt may be an Anglicised version of the French ‘nos amis’ but is probably derived from the appelation ‘Uncle Sam’.
1925		(con. WWI) Fraser & Gibbons Soldier and Sailor Words 250: Sammies, The: A name in the war for the U.S. Army troops serving in Europe. On America joining the Allies, a Daily News correspondent, shortly before the first U.S. troops arrived, protested against the application to them of the name ‘Yankees’; ’Do not call them Yankees, none of them like it’. Punch thereupon (June 13th, 1917), suggested Sammies – ‘As a term of distinction and endearment . . . after their Uncle’. The name was adopted popularly in England, only, however, to be dropped after a time. Said an American General in France ‘If there is one thing the American soldier dislikes, it is to be called a ‘Sammy’.’.
1934		(con. 1920s) J.T. Farrell Young Manhood in Studs Lonigan (1936) 180: If he was only a Sammy now, in Paris, celebrating the Armistice.

3. (US milit., also skinny) a derog. name for a Somali.

1999

N.Y. Rev. of Books 18 Nov. 27: They had a sovereign contempt for the Somalis, whom they called ‘skinnies’ or ‘sammies’.

4. (UK black/gang, also sam, sams) a Samurai sword.

2018		KO ‘9er Ting’ 🎵 Fuck-off Sammy, ride out to London Fields with a bally.
2018-20		T. Thorne (ed.) ‘Drill Slang Glossary’ at Forensic Linguistic Databank 🌐 Sam, sams, sammy - samurai sword or large knife.

5. see portsammy n.