Longman Dictionary of Contemporary English
Wiktionary
n. An exhibition at which members of a specific industry exhibit or demonstrate their products to prospective customers and to each other
Wikipedia
A trade fair (trade show, trade exhibition, or expo) is an exhibition organized so that companies in a specific industry can showcase and demonstrate their latest products and services, meet with industry partners and customers, study activities of rivals, and examine recent market trends and opportunities. In contrast to consumer fairs, only some trade fairs are open to the public, while others can only be attended by company representatives (members of the trade, e.g. professionals) and members of the press, therefore trade shows are classified as either "public" or "trade only". A few fairs are hybrids of the two; one example is the Frankfurt Book Fair, which is trade only for its first three days and open to the general public on its final two days. They are held on a continuing basis in virtually all markets and normally attract companies from around the globe. For example, in the U.S., there are currently over 10,000 trade shows held every year, and several online directories have been established to help organizers, attendees, and marketers identify appropriate events.
Usage examples of "trade fair".
With more than a single ship, we can tell Nordla, Austra, and the other traders that either they trade fair and square or we seize or sink their ships.
I then remembered he had been at the trade fair at Shapur, where I had first learned of the pearl swamps.