sentences:  Yars does not appear to be a Russian word but the Slavic root яр ("yar") is present, being a "bank" or "steep ravine", consistent with the nomenclature of another newly fielded Russian missile, the RS-26 Rubezh (РС-26 Рубеж) meaning a "boundary" or "outer limit".According to Sergey Karakaev, commander of the Strategic Missile Forces, "Yars" is an acronym for "Yadernaya Raketa Sderzhivaniya" (), meaning "Nuclear Deterrence Rocket".Asserted by the Russian government as being designed to defeat present and potential anti-missile systems, the ICBM was first tested by a launch from a mobile launcher at the Plesetsk Cosmodrome in northwestern Russia at 11