A flea market is a type of outdoor market where people sell secondhand or used goods, as well as handmade crafts, antiques, and other items. The term "flea" refers to the fact that many of the items sold at these markets may have previously belonged to someone else and may have been infested with fleas.

Flea markets are usually held on weekends or holidays, and vendors typically rent booths or tables to display and sell their wares. Some flea markets also have food vendors and other types of entertainment to attract visitors.

Flea markets are popular with bargain hunters, collectors, and people looking for unique or unusual items. They can be found in many cities and towns around the world, and some of the most famous flea markets include the Portobello Road Market in London, the Saint-Ouen flea market in Paris, and the Rose Bowl Flea Market in Los Angeles.