actinon Actinomyxidiida • Actinonema · · · Info · Definitions · Synonyms · Characters · · actinon · · Text Latin · · Script 7 · · Length Definitions · · · (noun) any of a series of radioactive elements with atomic numbers 89 through 103. Synonyms: actinoid, actinide. · · Noun Definition 1 Synonyms · · · actinoid · · Synonym 1 actinide · · Synonym 2 Characters · · a latin small letter a U+0061 c latin small letter c U+0063 i latin small letter i U+0069 n latin small letter n U+006E o latin small letter o U+006F t latin small letter t U+0074