Green’s Dictionary of Slang

1. (US Und., also scatter gun) a musket [? the shot scatters once it leaves the weapon].

1848		Ladies’ Repository (N.Y.) Oct. VIII:37 317/1: Scatter, a musket, or shot gun.
1936		R.F. Adams Cowboy Lingo 166: Shotguns were called ‘scatter guns’.

2. anywhere that addicts frequent in order to buy drugs and socialize.

1914		Wash. Post 11 Nov. Misc. 3/5: Toledo was known as a ‘right town’ and a good place to hide out in with its numerous ‘scatters’ or dives where ‘hop’ or ‘grease’ was smoked.
1959		J.E. Schmidt Narcotics Lingo and Lore.

3. (US) a bar, saloon, nightclub or speakeasy where one can purchase alcoholic drinks; similarly used of a drug centre.

1928		C. Panzram Journal of Murder in Gaddis & Long (2002) 116: Catting up a scatter or ginmill—to hold up a saloon.
1930		G. Milburn ‘Me and My Bindle’ in Hobo’s Hornbook 262: So I slipped down to a scatter to lap a shot of corn.
1935		W. Mahoney ‘The Ruse in Cocaine Alley’ in Und. Detective Mar. 🌐 [...] he said, jerking a thumb toward the cottage, ‘Sammy Mondell’s scatter.’ [...] The abode of Sammy Mondell [...] was well known as a favorite hangout of dope peddlers.
1938		D. Runyon ‘A Job for the Macarone’ in Runyon on Broadway (1954) 690: A little scatter on Biscayne Boulevard.
1940		D. Maurer Big Con 162: You could get any kind of a stick you needed in Dan’s scatter.
1950		Goldin et al. DAUL 185/1: Scatter. A rendezvous for thieves, especially a place where drinks are sold.

4. a place; a room.

1935		A.J. Pollock Und. Speaks n.p.: Scatter, a small, cheap lodging house.
1938		D. Runyon ‘Sense of Humor’ in Runyon on Broadway (1954) 272: Joe the Joker [...] starts telling me about a little scatter that he has up in Harlem.
1943		R. Chandler Lady in the Lake (1952) 207: Don’t bother to call your house-peeper and send him up to the scatter.