WordNet (r) 3.0 (2006):

darmstadtium
    n 1: a radioactive transuranic element [syn: darmstadtium,
         Ds, element 110, atomic number 110]

The Elements (07Nov00):

darmstadtium
Symbol: Ds
Atomic number: 110
Atmic weight: 281
Darmstadtium, formerly known as ununnilium, is placed as the heaviest
member of group 10 but a sufficiently stable isotope is not known which
would allow chemical experiments to confirm its place. This synthetic
element is one of the so-called super-heavy atoms and was first
synthesized
in 1994. The longest-lived and heaviest isotope known is 281Ds with
a half-life of ~10 s although a possible isomer, 281bDs has an
unconfirmed
half-life of about 4 minutes.
Element 110 was first given the temporary name ununnilium (symbol Uun).
Once recognized as discoverers, the team at GSI considered the names
darmstadtium (Ds) and wixhausium (Wi) for element 110. They decided on
the former and named the element after the city near the place of its
discovery, Darmstadt and not the suburb Wixhausen itself. The new name
was officially recommended by IUPAC on August 16, 2003.