Green’s Dictionary of Slang

1. (US) a handgun.

1914		Jackson & Hellyer Vocab. Criminal Sl. 72: roscoe [...] a revolver [...] ‘Stash your roscoe before you come back to the kip.’.
1926		Times Despatch (Richmond, VA) 17 Oct. 7/7: Rosco — A gun.
1929		C.G. Givens ‘Chatter of Guns’ in Sat. Eve. Post 13 Apr.; list extracted in AS VI:2 (1930) 134: roscoe, n. Pistol.
1931		D. Runyon ‘Dream Street Rose’ in Runyon on Broadway (1954) 57: My friend outs with a large John Roscoe.
1933		N. Algren ‘So Help Me’ in Texas Stories (1995) 25: It is all very well for you to say that one roscoe is enough when you are carryin’ it.
1936		R.L. Bellem ‘Falling Star’ in Spicy Detective Sept. 🌐 The roscoe said: ‘Chow!’ and spat a streak of flame past my ear.
1938		Smith’s Wkly (Sydney) 26 Feb. 3/3: The gent only used one hand to greet Mr. Gardner. He had a ‘roscoe’ in the other and it went off and killed ‘Hoppy’.
1944		C.B. Davis Rebellion of Leo McGuire (1953) 169: We’ve got enough left to [...] get us each a cheap roscoe.
1952		(con. 1920s) ‘Harry Grey’ Hoods (1953) 69: I nodded. Patsy patted his Roscoe.
1966		R.E. Alter Carny Kill (1993) 122: ‘Do I get the Roscoe?’ [...] he passed over the weapon. It was a fortyfive, a Colt.
1974		V.E. Smith Jones Men 26: I know three men [...] best I ever seen with a roscoe.
1985		T.R. Houser Central Sl. 45: rosco A handgun.
1988		T. Harris Silence of the Lambs (1991) 244: Krendler told me to turn in my ID and the roscoe.
1990		Tupper & Wortley Aus. Prison Sl. Gloss. 🌐 Roscoe/rosca. Hand gun.
1992		Bentley & Corbett Prison Sl. 88: Roscoe A handgun or pistol.
1995		Souls of Mischief ‘Ya Don’t Stop’ 🎵 Always wanna pull they roscoes instead of hoes.
2001		D. Looser Boobslang [U. Canterbury D.Phil. thesis] 156/1: roscoe n. a firearm.
2006		G. Pelecanos Night Gardener 108: I always carry when I work. You gonna need a roscoe too.
2015		P. Doyle (con. 1969-1973) Big Whatever 23: Why would mellow cat Mel Parker own a fucking roscoe?
2021		J. Ellroy Widespread Panic 15: A Mex busboy [...] saw my roscoe and got the shiver-shakes.

2. (US) a man.

1914

Ade ‘The New Fable of the Speedy Sprite’ in Ade’s Fables 29: That evening she had four throbbing Roscoes curled up among her Sofa Pillows.

3. the penis.

2013

C. Manson in Rolling Stone 21 Nov. 🌐 You think I’m too old to jack off. [...] But I’m not. I’m still active with my roscoe. I’m still me.