octane number octahedron group • octave flute · · · Info · Definitions · Characters · · octane number · · Text Common · · Latin · · Scripts 13 · · Length Definitions · · · (noun) a measure of the antiknock properties of gasoline. Synonyms: octane rating. · · Noun Definition 1 Characters · · space U+0020 a latin small letter a U+0061 b latin small letter b U+0062 c latin small letter c U+0063 e latin small letter e U+0065 m latin small letter m U+006D n latin small letter n U+006E o latin small letter o U+006F r latin small letter r U+0072 t latin small letter t U+0074 u latin small letter u U+0075