a horizon a great deal • a hundred times · · · Info · Definitions · Characters · · a horizon · · Text Common · · Latin · · Scripts 9 · · Length 4 · · Syllables Definitions · · · (noun) the top layer of a soil profile; usually contains humus. Synonyms: A-horizon, A horizon. · · Noun Definition 1 Characters · · space U+0020 a latin small letter a U+0061 h latin small letter h U+0068 i latin small letter i U+0069 n latin small letter n U+006E o latin small letter o U+006F r latin small letter r U+0072 z latin small letter z U+007A