Trade means to exchange one thing for another. When you trade baseball cards with a friend, you might swap your duplicate cards for ones you need to complete your collection. When you trade your sandwich for your friend's chips at lunch, both of you get something you want more than what you gave up.

Trade happens everywhere, from school lunchrooms to international shipping ports. Countries trade with each other constantly: Japan might trade electronics to America in exchange for wheat and soybeans. Ancient civilizations traded goods along famous routes like the Silk Road, exchanging silk, spices, gold, and ideas across thousands of miles.

The word can also mean a skilled profession, especially one requiring manual work and specialized training. A carpenter, plumber, or electrician practices a trade. These tradespeople learn their skills through years of hands-on experience and apprenticeship. Someone might say they're “learning a trade” when they're studying to become an expert in this kind of skilled work.

When used as a noun, trade can mean the business of buying and selling: “She works in the book trade” means she's in the business of publishing or selling books. Trade can also describe a pattern of business or customers, like when a restaurant loses trade because a new competitor opens nearby.