to have a good knowledge of someone or something. (*Typically: be ~; become ~; get ~.) Are you familiar with changing a flat tire? I can't speak German fluently, but I'm somewhat familiar with the language.
Fig. [for a story or an explanation] to sound familiar. Your excuse has a familiar ring. Have you done this before?This term paper has a familiar ring to it. I think it has been copied.
to seem as if you have heard it or experienced it before Passing notes to friends in class may have a familiar ring to it, but these days students use text messages on their phones to send forbidden messages.