• synonyms


[uh-nuh-nuhn-ee-uh m]
noun Chemistry, Physics.
  1. former name of roentgenium. Symbol: Uuu
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Also called element 111.


[rent-gen-ee-uh m, -jen-, ruhnt-]
noun Chemistry, Physics.
  1. a superheavy, synthetic radioactive element with a very short half-life. Symbol: Rg; atomic number: 111.
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Origin of roentgenium

named after German physicist Wilhelm Konrad Roentgen; see -ium
Formerly unununium, element 111.

element 111

noun Chemistry, Physics.
  1. roentgenium.
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Formerly unununium.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018