praseodymium (n.)youdaoicibaDictYouDict
rare metallic element, 1885, coined in Modern Latin by discoverer Carl Auer von Welsbach (1858-1929) from Greek prasios "leek-green" (from prason "leek") + didymos "double," the name given to an earth in 1840, so called because it was a "twin" to lanthana. When didymia was further analyzed in the 1880s, it was found to have several components, one of which was characterized by green salts and named accordingly, with the elemental suffix -ium.
thallium (n.)youdaoicibaDictYouDict
rare metallic element, 1861, Modern Latin, from Greek thallos "young shoot, green branch" (see thallus) + element name ending -ium. So called by its discoverer, Sir William Crookes (1832-1919), from the green line in its spectrum by which he detected it. Related: Thallic.
thorium (n.)youdaoicibaDictYouDict
rare metallic element, 1832, Modern Latin, named by its discoverer, Swedish chemist Jöns Jakob Berzelius (1779-1848) from thorite (silicate of thorium), the name of a mineral found in Norway from which it was extracted (which Berzelius also had named, as thoria, in 1828), and named in honor of the Scandinavian god Thor. With chemical ending -ium.
tungsten (n.)youdaoicibaDictYouDict
rare metallic element, 1796, from Swedish tungsten "calcium tungstate," coined 1780 by its discoverer, Swedish chemist Karl Wilhelm Scheele (1742-1786) from tung "heavy" + sten "stone" (see stone (n.)). The word was used earlier as the name for calcium tungstate (1770). Atomic symbol W is from Latin wolframium, from German Wolfram "iron tungstate" (see wolfram).
uranium (n.)youdaoicibaDictYouDict
rare metallic element, 1797, named 1789 in Modern Latin by its discoverer, German chemist and mineralogist Martin Heinrich Klaproth (1743-1817), for the recently found planet Uranus (q.v.) + element ending -ium.
vanadium (n.)youdaoicibaDictYouDict
rare metallic element, 1833, named 1830 by Swedish chemist Nils Gabriel Sefström (1787-1845), from Old Norse Vanadis, one of the names of the Norse beauty goddess Freyja (perhaps from PIE *wen- (1) "to desire, strive for," which would connect it to Venus); the metal perhaps so called for of its colorful compounds (an earlier name for it was erythronium, for the redness of its salts when heated). Related: Vanadous; vanadious.