General English

General Science


  • A silver-white radioactive metallic element whose atomic number is 92. It is very dense, malleable, and ductile, and is a poor conductor of electricity. It is highly reactive, extremely toxic, and has over 20 known isotopes, all unstable. Its applications include its use as a source of nuclear power, and for conversion into plutonium. Its chemical symbol is U.
  • chemical symbolU

Origin & History of “uranium”

Ouranós was an ancient sky god in Greek mythology, consort of Gaea and father of Cronos and the Titans (his name was a personification of Greek ouranós ‘heaven’). The Romans called him ūranus, and the name soon came to be applied to the seventh planet from the sun after it was discovered in 1781. (Its discoverer, the German-born British astronomer Sir William Herschel, originally named it Georgium sidus ‘Georgian planet’, as an obsequious compliment to king George III, and others suggested that it should be called Herschel after the man who found it, but in the end the customary practice of naming after a classical deity prevailed.) The term uranium was derived from the planet’s name in 1789 by the German chemist Martin Klaproth, and is first recorded in English in 1797.