CXVIII is the Roman numeral representation for the number 118. In the context of chemistry, it refers to the element with atomic number 118, known as oganesson. Oganesson is a synthetic element and is classified as a noble gas, although it exhibits properties that differ from other elements in this group. Discovered in 2002 by a team of Russian and American scientists, oganesson is named after the physicist Yuri Oganessian. Due to its instability and rarity, it has no significant commercial applications and is primarily of interest for scientific research in the field of nuclear physics.