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1.
(ECONOMICS) the effective ratio whereby a country exchanges its goods with those of another country. Hence, a country that exports (say) mostly coffee and chocolate has to import almost everything else; if the price of chocolate and coffee declines, the country has no choice but to increase production of both, further reducing the price of both on world markets, and increasing the relative cost of everyhting it imports.

Terms of trade are determined notionally by the forex markets, but more fundamentally by (a) the markets for commodities, and (b) the ability of the country to finance transitions to other, higher-priced export goods.
Terms of trade typically lead to very high real exchange rates for currencies like the Indian rupee.
by Abu Yahya May 17, 2010