PHENOTHIAZINE Meaning of PHENOTHIAZINE in English [ ˌfi:nəʊ'θʌɪəzi:n , ˌfɛnəʊ- ]■ noun Chemistry a synthetic compound used to treat parasitic infestations of animals, or one of its derivatives, used as tranquillizers. Concise Oxford English vocab. Сжатый оксфордский словарь английского языка. 2004