Upside down b - which if you look at it as a lower case, means p, or methamphetamine. This is a common term used in New Zealand, made famous by Bro'Town.
The letter p is likely to be derived from the main ingredient in methamphetamine, pseudoephedrine.
Eh bro'! I can't believe youse got hooked on upside-down b!
by Rebelmonkeys October 2, 2006
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