What element has the symbol 'Db'?

The story behind the answer

Db stands for Dubnium, element 105. It’s a synthetic, highly radioactive transactinide named after Dubna, Russia, home of the Joint Institute for Nuclear Research, which first reported its creation. A naming dispute with a U.S. team (who proposed “hahnium”) was settled by IUPAC in 1997, adopting Dubnium. Chemically, it sits in group 5, like niobium and tantalum, but only exists in fleeting isotopes used for research.

Memory tip: Db = DuBna/DuBnium. Don’t confuse it with Darmstadtium (Ds) or Dysprosium (Dy), and “Diborium” isn’t an element.