fourth dimension fourth-class • fourth-dimensional · · · Info · Definitions · Synonyms · Characters · · fourth dimension · · Text Common · · Latin · · Scripts 16 · · Length Definitions · · · (noun) the fourth coordinate that is required (along with three spatial dimensions) to specify a physical event. Synonyms: time. · · Noun Definition 1 Synonyms · · · one-fourth · · Synonym 1 fourth · · Synonym 2 one-quarter · · Synonym 3 quarter · · Synonym 4 fourth part · · Synonym 5 twenty-five percent · · Synonym 6 quartern · · Synonym 7 4th · · Synonym 8 quaternary · · Synonym 9 fourthly · · Synonym 10 Characters · · space U+0020 d latin small letter d U+0064 e latin small letter e U+0065 f latin small letter f U+0066 h latin small letter h U+0068 i latin small letter i U+0069 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 s latin small letter s U+0073 t latin small letter t U+0074 u latin small letter u U+0075