Green’s Dictionary of Slang

tinnie n.

also tinny

1. [1960s+] (orig. Aus. surfing) a can of beer.

2. [1970s+] (Aus.) a small aluminium boat.

3. [1980s+] (N.Z. drugs) silver foil, used for wrapping measures of cannabis; thus the measure of cannabis as sold as a single unit.

In compounds

tinnie house (n.)

a house or apartment used for cannabis sales.