thirtieth(the ordinal form of the number thirty, see also: 30th) adjective [UK: ˈθɜː.tɪəθ] [US: ˈθɝː.tiəθ]He died on his thirtieth birthday. = Morì nel suo trentesimo compleanno.
trentesimonoun {m}
thirtieth(the person or thing in the thirtieth position) noun [UK: ˈθɜː.tɪəθ] [US: ˈθɝː.tiəθ]He died on his thirtieth birthday. = Morì nel suo trentesimo compleanno.