bohrium

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun An artificially produced radioactive element with atomic number 107 for which isotopes have been observed with mass numbers ranging from 260 to 275, all of which decay by alpha-particle emission. The isotope with mass number 264 has the longest confirmed half-life (1.3 seconds), although longer half-lifes have been reported for some of its heavier isotopes. cross-reference: Periodic Table.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun A transuranic chemical element (symbol Bh) with an atomic number of 107.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun a transuranic element