PROTOTHERIAN Meaning of PROTOTHERIAN in English prototherian BrE AmE ˌprəʊt əʊ ˈθɪər i‿ən ◂ AmE \ ˌproʊt̬ ə ˈθɪr-▷ prototherian|s z Longman Pronunciation English Dictionary. Английский словарь произношений Longman. 2012