ruthenium

noun

ru·​the·​ni·​um rü-ˈthē-nē-əm 

: 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

Even with only 1% ruthenium by weight, the electrode reduced overpotential by about 25% compared to conventional cobalt-molybdenum catalysts. —Aamir Khollam, Interesting Engineering, 14 Aug. 2025

In search of more definitive evidence, Willbold’s team zeroed in on an element named ruthenium. —Quanta Magazine, 4 Aug. 2025

There are also the Mobius strip cuff links crafted from all-silver or interwoven yellow-gold, rhodium and black ruthenium or semiprecious chrysocolla or spiny oyster. —Jean E. Palmieri, Footwear News, 1 Aug. 2025

Yellow gold, rose gold and ruthenium give the brass an extra glimmer (some things that glitter are gold, after all). —Erik Kain, Forbes.com, 12 June 2025

Word History

Etymology

New Latin, from Medieval Latin Ruthenia Ruthenia

First Known Use

1829, in the meaning defined above

Rhymes for ruthenium

• asplenium
• delphinium
• perineum
• proscenium
• selenium
• vaccinium
• rhenium

Kids Definition

ruthenium

noun

ru·​the·​ni·​um rü-ˈthē-nē-əm 

: a hard brittle grayish rare metallic element used especially in alloys and catalysts see element

Medical Definition

ruthenium

noun

ru·​the·​ni·​um rü-ˈthē-nē-əm 

: a hard brittle grayish polyvalent rare metallic element occurring in platinum ores and used in hardening platinum alloys

—symbol Ru see Chemical Elements Table