commoncommoncommons2nouna piece of land that everybody can use: We went for a walk on the common.have something in commonto be like somebody in a certain way, or to have the same interests as somebody: Paul and I are good friends. We have a lot in common.commoncommoncommonercommonest1adjective (commoner, commonest)1happening often or found in many places: Jackson is a common English name.oppositerare2shared by two or more people or by everybody in a group: They share a common interest in photography.