actinoid actinography • Actinoida · · · Info · Definitions · Synonyms · Characters · · actinoid · · Text Latin · · Script 8 · · Length Definitions · · · (noun) any of a series of radioactive elements with atomic numbers 89 through 103. Synonyms: actinide, actinon. · · Noun Definition 1 (adj) having a radial form. Example: "Starfish are actinoid--that is, they are radially symmetrical." · · Adjective Definition 1 Synonyms · · · actinide · · Synonym 1 actinon · · Synonym 2 Characters · · a latin small letter a U+0061 c latin small letter c U+0063 d latin small letter d U+0064 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