SEVENTIETH Meaning of SEVENTIETH in English seventieth BrE AmE ˈsev ə nt i‿əθ ɪθ AmE \ ˈsev ə n t̬ - —Casually also ⇨ˈseb m p t i‿əθ▷ seventieth|s s Longman Pronunciation English Dictionary. Английский словарь произношений Longman. 2012