An artificially produced radioactive element with atomic number 105. The isotope with mass number 262 has the longest confirmed half-life (35 seconds), although longer half-lifes have been reported for some of its heavier isotopes.
A radioactive chemical element with a very short half-life: a transactinide produced by bombarding californium or berkelium with high-energy nuclear particles: symbol, Db; at. no. 105
A synthetic, radioactive element that is produced from californium, americium, or berkelium. Its most long-lived isotopes have mass numbers of 258, 261, 262, and 263 with half-lives of 4.2, 1.8. 34, and 30 seconds, respectively. Atomic number 105.
Origin of dubnium
After Dubna , Russia, location of the United Institute of Nuclear Research