Sentence:  This <WSD>trade</WSD> was subject to a tariff of 7.5 per cent after February 1835 , but much was smuggled into Assiniboia with the result that the duty was reduced by 1841 to 4 per cent on the initiative of the London committee . 
Meaning of the word marked with <WSD> tags:  the commercial exchange (buying and selling on domestic or international markets) of goods and services