promethium

noun

pro·me·thi·um prə-ˈmē-thē-əm

: a radioactive metallic element of the rare-earth group obtained as a fission product of uranium or from neutron-irradiated neodymium see Chemical Elements Table

Example Sentences

Recent Examples on the Web Yttrium is twice as abundant as lead; all of the rare-earth metals (with the exception of radioactive promethium) are more common than silver. —

Hugh Aldersey-williams, Discover Magazine, 21 Sep. 2011 Carl Sagan and Iosef Shklovskii, along with Frank Drake, had raised the idea of looking for radioactive elements like promethium in stars as a possible alien signal. —

Corey S Powell, Discover Magazine, 1 July 2017 One promethium isotope, with eighty-eight neutrons, has a half-life of a few days; the other, with eighty-six neutrons, has a half-life of a few years. —

Neima Jahromi, The New Yorker, 27 Dec. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'promethium.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.