seventeenth(ordinal number, see also: 17th) adjective [UK: ˌsevn.ˈtiːnθ] [US: ˈse.vən.ˈtiːnθ]Yesterday was my seventeenth birthday. = Ieri era il mio diciassettesimo compleanno.
diciassettesimonoun {m}
seventeenth(one of seventeen equal parts of a whole) noun [UK: ˌsevn.ˈtiːnθ] [US: ˈse.vən.ˈtiːnθ]Yesterday was my seventeenth birthday. = Ieri era il mio diciassettesimo compleanno.