Deja Entendu

Deja entendu is the sensation of having heard something even if the details are unclear or even imaginary. Meaning "already heard" in French, it is a false sense of familiarity upon hearing something novel and the feeling that you have heard it before. Probably the most common example would be hearing a new song on the radio that has just enough familiarity to another piece to make one feel that they have heard it before.