epon·y·my \ ̷ ̷ˈ ̷ ̷nəmē\noun (-es) Etymology: Greek epōnymia, from epōnymos + -ia -y 1.orepon·y·mism\-nəˌmizəm\[eponymism from eponym + -ism]: the explanation of a proper name (as of a tribe or town) by supposing it to be derived from a fictitious eponym 2.: eponymate