humic substance humic shale • humicubation · · · Info · Definitions · Characters · · humic substance · · Text Common · · Latin · · Scripts 15 · · Length 4 · · Syllables Definitions · · · (noun) an organic residue of decaying organic matter. Synonyms: humic substance. · · 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 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 s latin small letter s U+0073 t latin small letter t U+0074 u latin small letter u U+0075