Zor ‧ o ‧ as ‧ ter /ˌzɒrəʊˈæstə $ ˈzɔːrəʊæstər/ BrE AmE ( also Zarathustra )
(?628-?551 BC) a Persian religious teacher and ↑ prophet (=someone whom people believe has been sent by God to lead and teach them) who started a new religion called ↑ Zoroastrianism