OCTANE Meaning of OCTANE in English ■ noun Chemistry a liquid hydrocarbon of the alkane series, present in petroleum spirit. [C 8 H 18 .]OriginC19: from octo- 'eight' (denoting eight carbon atoms) + -ane 2 . Concise Oxford English vocab. Сжатый оксфордский словарь английского языка. 2004