Green’s Dictionary of Slang

1. injectable amphetamine.

1972		Smith & Gay Heroin in Perspective.
2001		ONDCP Street Terms 22: Water — methamphetamine.

2. phencyclidine.

1985		T.R. Houser Central Sl. 53: trippin’ [...] ‘Dude took some of that water; he be trippin’.’ [Ibid.] 55: under the water wing. Under the influence of PCP. [Ibid.] 57: watered-up To be high on PCP.
2003		Microgram Bulletin XXXVI:8 182: PCP combined with marijuana is referred to as Killer Joints, Super Grass, Fry, Lovelies, Wets, and Waters. Today, PCP joints are often referred to as ‘dippers’ because users dip the joints into a PCP-laced liquid referred to as ‘water.’.

3. furanon di-hydro, used medically to encourage sleep and assist muscle recovery and growth.

1999

Toronto Sun 31 Dec. 82: Gugliotta’s seizure probably was caused by an over-the-counter dietary supplement with furanon di-hydro in it. The substance, which has street slang names such as ‘water’ and ‘liquid,’ is supposed to encourage sleep and assist muscle recovery and growth.

4. gamma hydroxybutyrate.

2001

ONDCP Street Terms 22: Water — [...] Gamma hydroxybutyrate (GHB).