atomic number 85 atomic number 84 • atomic number 86 · · · Info · Definitions · Synonyms · Characters · · atomic number 85 · · Text Common · · Latin · · Scripts 16 · · Length 9 · · Syllables Definitions · · · (noun) a highly unstable radioactive element (the heaviest of the halogen series); a decay product of uranium and thorium. Synonyms: astatine, At, atomic number 85. · · Noun Definition 1 Synonyms · · · astatine · · Synonym 1 at · · Synonym 2 Characters · · space U+0020 5 digit five U+0035 8 digit eight U+0038 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 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 t latin small letter t U+0074 u latin small letter u U+0075