ammonium alum ammonium • ammonium amalgam · · · Info · Definitions · Synonyms · Characters · · ammonium alum · · Text Common · · Latin · · Scripts 13 · · Length 6 · · Syllables Definitions · · · (noun) a white crystalline double sulfate of aluminum: the ammonium double sulfate of aluminum. Synonyms: alum, ammonia alum, ammonium alum. · · Noun Definition 1 Synonyms · · · alum · · Synonym 1 ammonia alum · · Synonym 2 Characters · · space U+0020 a latin small letter a U+0061 i latin small letter i U+0069 l latin small letter l U+006C m latin small letter m U+006D n latin small letter n U+006E o latin small letter o U+006F u latin small letter u U+0075