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roentgenium

[rent-gen-ee-uh m, -jen-, ruhnt-]

noun Chemistry, Physics.

a superheavy, synthetic radioactive element with a very short half-life. Symbol: Rg; atomic number: 111.

Origin of roentgenium

named after German physicist Wilhelm Konrad Roentgen; see -ium

Formerly unununium, element 111.

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019