The business of buying and selling commodities; commerce. See Synonyms at business. The people working in or associated with a business or industry: a textile-exporting publication for the trade. The customers of a specified business or industry; clientele. The act or an instance of buying or selling; transaction. An exchange of one thing for another. An occupation, especially one requiring skilled labor; craft: the building trades, including carpentry, masonry, plumbing, and electrical installation. The trade winds. Often used in the plural with the. To engage in buying and selling for profit. To make an exchange of one thing for another. To be offered for sale: Stocks traded at lower prices this morning. To shop or buy regularly: trades at the local supermarket. To give in exchange for something else: trade farm products for manufactured goods; will trade my ticket for yours. To buy and sell (stock, for example). To pass back and forth: We traded jokes. Of or relating to trade or commerce. Relating to, used by, or serving a particular trade: a trade magazine. Of or relating to books that are primarily published to be sold commercially, as in bookstores. trade down To trade something in for something else of lower value or price: bought a new, smaller car, trading the old one down for economy. trade in To surrender or sell (an old or used item), using the proceeds as partial payment on a new purchase. trade on To put to calculated and often unscrupulous advantage; exploit: children of celebrities who trade on their family names. trade up To trade something in for something else of greater value or price: The value of our house soared, enabling us to trade up to a larger place.