- former name of meitnerium. Symbol: Une
Also called element 109.
- a superheavy, synthetic, radioactive element. Symbol: Mt; atomic number: 109.
Origin of meitnerium
Formerly unnilennium, element 109.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
- a synthetic element produced in small quantities by high-energy ion bombardment. Symbol: Mt; atomic no: 109
C20: named after Lise Meitner
- A synthetic, radioactive element that is produced by bombarding bismuth with iron ions. Its most long-lived isotopes have mass numbers of 266 and 268 with half-lives of 3.4 milliseconds and 70 milliseconds, respectively. Atomic number 109. See Periodic Table.
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