The definition of a convention is a meeting or assembly of people who share a common interest or a convention is a method, practice, rule or custom. An example of convention is a national meeting of English teachers
A convention, in the sense of a meeting, is a gathering of individuals who meet at an arranged place and time in order to discuss or engage in some common interest. The most common conventions are based upon industry, profession, and fandom
a way in which something is usually done. "to attract the best patrons the movie houses had to ape the conventions and the standards of theatres"
an agreement between states covering particular matters, especially one less formal than a treaty. "the convention, signed by the six states bordering on the Black Sea, aims to prevent further pollution"