Sentence:  The average smoker used only four <WSD>"hoons</WSD>", leaving him 36 <WSD>"hoons</WSD>", nearly half an ounce, to sell on the black market. 
Meaning of the word marked with <WSD> tags:  A unit of weight (about 0.378125 of a gram, or 0.0133 of an ounce) used to measure opium in British-controlled parts of Asia; a candareen.