meitnerium

/maɪtˈnɪriəm/
noun
  1. A radioactive chemical element with the symbol Mt and atomic number 109. It is a synthetic metal that does not occur naturally.
    • Scientists study meitnerium to learn more about heavy elements.
    • Meitnerium was first created in 1982 by a German research team.
    • Only a few atoms of meitnerium have ever been produced in laboratories.