direct sum directrix • direct support · · · Info · Definitions · Characters · · direct sum · · Text Common · · Latin · · Scripts 10 · · Length 3 · · Syllables Definitions · · · (noun) a union of two disjoint sets in which every element is the sum of an element from each of the disjoint sets. Synonyms: direct sum. · · Noun Definition 1 Characters · · space U+0020 c latin small letter c U+0063 d latin small letter d U+0064 e latin small letter e U+0065 i latin small letter i U+0069 m latin small letter m U+006D 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