Green’s Dictionary of Slang

angel dust n.

(drugs)

1. [1960s+] anything smokeable, e.g. tobacco, marijuana, parsley, mixed with phencyclidine.

2. [1970s] a mixture of cocaine, heroin and morphine, which can be smoked or injected.

3. [1970s] finely chopped marijuana.

4. [1970s+] (also angel’s dust) phencyclidine.

In compounds

angel dust hero (n.)

[1980s+] (US) a regular user of cocaine.