Green’s Dictionary of Slang

1. a metaphorical part of the body.

1910		Wodehouse Psmith in the City (1993) 114: Had he not unfortunately dislocated the radius bone of his bazooka while training.
1914		Bateman & Trevor [perf. Harry Champion] ‘Dr Shelley’ 🎵 He cried, ‘Oh doctor come at once, me hen is on her back / She's twisted her bazooka and she cannot get it back’.
1976		(ref. to 1930s) R. Barnes Coronation Cups and Jam Jars 106: Oh, doctor, Come at once, / The hen she’s on her back. / She’s twisted her bazooker / And cannot get it back.

2. the buttocks; in up the bazooka

3. the head, the mind, with implications of stupidity.

1939		Wodehouse Uncle Fred in the Springtime 127: ‘If you have nothing else to do at the moment, you might be trying that [thought] over on your bazooka’.
1954		Wodehouse Jeeves and the Feudal Spirit 125: Try that one on your bazooka, my dear Cheesewright.

4. the penis.

1970		C. Brown Down All the Days 155: And would you kindly take your eyes off my bazooka?
1985		B. Humphries Traveller’s Tool 107: The occasional little stewardess who has rashly settled for a bottom-of-the-range Cartier watch and a Bedouin bazooka up her back bottie.

5. (US black) an especially large and potent marijuana cigarette, laced with cocaine [note basuco n.].

2001

ONDCP Street Terms 2: Bazooka — [...] crack and tobacco combined in a joint.

6. (drugs) cocaine, crack cocaine.

2001		ONDCP Street Terms 2: Bazooka — Cocaine; crack.
2009		P. Temple Truth 291: On any Friday, an army of couriers hand-delivered snort, bazooka [...] to bankers, brokers, lawyers, accountants [etc.].

7. (US drugs) a cigarette that mixes coca paste and tobacco.

1990		Morn. Call (Allentown, PA) 24 May 38/1: ‘Bazooka’ — joint laced with coca paste.
2001		ONDCP Street Terms 2: Bazooka — [...] coca paste and marijuana.