lanthanon lanthanoid • lanthanotidae · · · Info · Definitions · Synonyms · Characters · · lanthanon · · Text Latin · · Script 9 · · Length 3 · · Syllables Definitions · · · (noun) any element of the lanthanide series (atomic numbers 57 through 71). Synonyms: rare earth, rare-earth element, lanthanoid, lanthanide. · · Noun Definition 1 Synonyms · · · rare earth · · Synonym 1 rare-earth element · · Synonym 2 lanthanoid · · Synonym 3 lanthanide · · Synonym 4 Characters · · a latin small letter a U+0061 h latin small letter h U+0068 l latin small letter l U+006C n latin small letter n U+006E o latin small letter o U+006F t latin small letter t U+0074