oganesson
noun
oga·nes·son ˌō-gə-ˈne-ˌsän 
ˌä-
: a short-lived, artificially produced radioactive element that has 118 protons —symbol Og see Chemical Elements Table
Word History
Etymology
Yuri Tsolakovich Oganessian born 1933 Russian-Armenian physicist (Russian Jurij Colakovič Oganesjan, Armenian Yuri Cʼolaki Hovhannisyan) + -on, suffix of elements that are noble gases, as argon and xenon
First Known Use
2016, in the meaning defined above