/ ˈθɪərɪst; NAmE ˈθiːə-; ˈθɪr-/ (also the·or·et·ician / ˌθɪərəˈtɪʃn; NAmE ˌθiːə-; ˌθɪr-/) noun
a person who develops ideas and principles about a particular subject in order to explain why things happen or exist
/ ˈθɪərɪst; NAmE ˈθiːə-; ˈθɪr-/ (also the·or·et·ician / ˌθɪərəˈtɪʃn; NAmE ˌθiːə-; ˌθɪr-/) noun
a person who develops ideas and principles about a particular subject in order to explain why things happen or exist
Oxford Advanced Learner's English Dictionary. Оксфордский английский словарь для изучающик язык на продвинутом уровне. 2005