Green’s Dictionary of Slang

good n.

1. [mid–late 19C] (orig. US) alcohol; thus get good, to get drunk.

2. [1970s+] (drugs) phencyclidine.

3. [2000s] heroin.

4. [2000s] marijuana.

SE in slang uses

In phrases

do a bit of good for oneself (v.)

[1950s+] (Aus.) of a man, to seduce, to gain a woman’s sexual favours.

do oneself a bit of good (v.)

1. [late 19C] to make money (e.g. by a successful wager).

2. [1950s+] to improve one’s situation.