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ununnilium

American  
[uhn-uh-nil-ee-uhm] / ˌʌn əˈnɪl i əm /

noun

Chemistry, Physics.
  1. former name of darmstadtium. Uun


Etymology

Origin of ununnilium

From Latin ūn(us) “one” + ūn(us) “one” + nīl “nothing” + New Latin -ium; one ( def. ), nil, -ium