Definition of "berkelium" []

• A synthetic transuranic radioactive element having 9 isotopes with mass numbers from 243 to 250 and half-lives from 3 hours to 1,380 years. Atomic number 97; melting point 986°C; valence 3, 4. See Table at element. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "The team produced six atoms of the element by smashing together isotopes of calcium and a radioactive element called berkelium in a particle accelerator about 75 miles north of Moscow on the Volga River, according to a paper that has been accepted for publication at the journal Physical Review Letters."
• "A team from the US and Russia produced the elusive element 117 by fusing together atoms of calcium and another rare, heavy element known as berkelium, filling in the final gap on the list of observed elements up to 118."
• "The team produced six atoms of the element by smashing together isotopes of calcium and a radioactive element called berkelium in a particle accelerator about 75 miles north of Moscow on the Volga River, according to a paper that has been accepted for publication at the journal"