A lingua franca (/ˌlɪŋɡwə ˈfræŋkə/; lit. ‘Frankish tongue’; for plurals see § Usage notes), also known as a bridge language, common language, trade language, auxiliary language, vehicular language, or link language, is a language systematically used to make communication possible between groups of people who do not share a native language or dialect, particularly when it is a third language that is distinct from both of the speakers’ native languages.
Actually Wikipedia specifically has a note at the top: