ru·​the·​ni·​um | \ rü-ˈthē-nē-əm How to pronounce ruthenium (audio) \

Definition of ruthenium

: a rare hard silvery-white metallic element occurring in platinum ores and used especially as a catalyst and to harden alloys — see Chemical Elements Table

Examples of ruthenium in a Sentence

Recent Examples on the Web The ruthenium atom is solidly attached to a base of molecular groups shaped like a five-petaled flower. Scientific American, "Nanomachines, Jellyfish Hugs and Hurricane Dorian From Space: The Week's Best Science GIFs," 30 Aug. 2019 The chemical element with the atomic number 44 is called ruthenium. Mark Inabinett,, "Watch Hank Aaron hit 715 on 44th anniversary of historic homer," 8 Apr. 2018 Battery materials such as cobalt and steel-hardener vanadium have surged, while minor precious metals like ruthenium rallied too. Thomas Biesheuvel,, "China Sends One of the West’s Most Critical Materials Soaring," 11 Sep. 2017 Rhodium, iridium and ruthenium count among the precious metals that are more rare than gold, according to the U.K.’s Royal Mint. Victor Reklaitis, WSJ, "How Much Do You Know About Gold Investing?," 4 May 2017 Combining a small amount of hydrogen brought from Earth with martian atmospheric carbon dioxide in the presence of a nickel or ruthenium catalyst would yield methane and water. David S. F. Portree, WIRED, "Making Rocket Fuel on Mars (1978)," 3 Nov. 2012 Researchers detected the behavior in a crystal of ruthenium trichloride at the Oak Ridge National Laboratory in Tennessee. Shannon Palus, Discover Magazine, "Electrons ‘Split’ in New Form of Matter," 22 Dec. 2016

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

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First Known Use of ruthenium

1829, in the meaning defined above

History and Etymology for ruthenium

New Latin, from Medieval Latin Ruthenia Ruthenia

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The first known use of ruthenium was in 1829

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Cite this Entry

“Ruthenium.” Dictionary, Merriam-Webster, Accessed 8 Aug. 2020.

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ru·​the·​ni·​um | \ rü-ˈthē-nē-əm How to pronounce ruthenium (audio) \

Medical Definition of ruthenium

: a hard brittle grayish polyvalent rare metallic element occurring in platinum ores and used in hardening platinum alloys symbol Ru — see Chemical Elements Table

More from Merriam-Webster on ruthenium

Rhyming Dictionary: Words that rhyme with ruthenium Encyclopedia article about ruthenium

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