Meitnerium is an extremely radioactive metal with a half-life of 4.5 seconds (Meitnerium 278). However, it is possible that the theroetical isotope Meitnerium 282 could have a half-life of about 67 seconds. Meitnerium was named after the co-discoverer of Protactinium; Lise Meitner. It was first synthesized by the GSI in 1982. It is predicted to have similar chemical properties to Iridium.

Meitnerium doesn't have many uses outside of research and exploration due to its instability.