[uhn-uh-nil-ee-uh m]

noun Chemistry, Physics.

former name of darmstadtium. Symbol: Uun

Nearby words

  1. untwist,
  2. untwisted,
  3. untypical,
  4. ununbium,
  5. ununhexium,
  6. ununoctium,
  7. ununpentium,
  8. ununquadium,
  9. ununseptium,
  10. ununtrium

Also called element 110.


[dahrm-stat-ee-uh m]

noun Chemistry, Physics.

a superheavy, synthetic, radioactive element with a very short half-life. Symbol: Ds; atomic number: 110.

Origin of darmstadtium

named after Darmstadt, the city in Germany where it was first created; see -ium

Formerly ununnilium, element 110.

element 110

noun Chemistry, Physics.

Formerly ununnilium.

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

Science definitions for ununnilium




A synthetic radioactive element, first produced by bombarding lead atoms with nickel atoms. It has a mass number of 281, and its most stable isotope has a half-life of over one minute. Atomic number 110. See Periodic Table.
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