贸易 (mào yì) means 'trade' or 'commerce' — the buying and selling of goods and services, especially between countries or regions. The character 贸 (mào) originally meant 'to trade' or 'to deal in goods', and is often associated with commerce and exchange. The character 易 (yì) means 'to exchange' or 'to change', reinforcing the core idea of mutual transfer of value. Together, they form a formal, standard term used in economics, business, and government contexts.

This word is commonly found in compound terms like 进出口贸易 (import-export trade), 对外贸易 (foreign trade), and 贸易伙伴 (trading partner). It appears frequently in news reports, policy documents, and business discussions — but is rarely used in casual daily speech, where simpler words like 买卖 (mǎi mài, 'buying and selling') are preferred. As a noun, it can function as a subject, object, or modifier, and typically requires context or modifiers to specify scope (e.g., 中美贸易, 'China–US trade').