Green’s Dictionary of Slang

1. (US drugs) cocaine.

1930		G. Milburn ‘The Dealer Gets It All’ in Hobo’s Hornbook 151: Soon my nerves set out to pling me for a snort o’ old snow ball.
1949		Monteleone Criminal Sl. (rev. edn) 216: snowball Cocaine.
2001		ONDCP Street Terms 20: Snowball — Cocaine and heroin.

2. (US drugs) a narcotic drug addict.

1949

(con. 1943–5) A. Murphy To Hell and Back (1950) 119: This woman’s a snowball [...] She’s fulla dope.

3. (US drugs) morphine.

1949

Monteleone Criminal Sl. (rev. edn) 216: snowball [...] morphine.

4. (US drugs) heroin .

1949		Monteleone Criminal Sl. (rev. edn) 216: snowball [...] heroin.
2001		see sense 1.

5. (UK drugs) MDMA [the white pill].

1994		I. Welsh ‘A Smart Cunt’ in Acid House 220: Eckys, I ask. Snowballs, he nods.
1999		Guardian 14 Oct. 12: Died of non-dependent use of drugs after taking a ‘snowball’ ecstasy tablet and speed.