ruthenium

noun

Etymology: Ruthenia + -ium. Named by Baltic German scientist Karl Ernst Claus in 1844 in honour of Russia (using the Latin name Ruthenia).

1. A metallic chemical element (symbol Ru) with an atomic number of 44.

   “Their latest catalyst includes some ruthenium.”

2. An atom of this element.

   “This reaction substitutes a ruthenium for an osmium.”