berkelium, n. [from the city of Berkeley, California, location of the University of California campus where it was discovered.].
a chemical element of the transuranic series. Chemical symbol Bk; atomic number 97; atomic weight 247. It is a radioactive element, with no stable isotopes; the longest-lived isotope is of mass number 247.07, decaying by alpha-emission with a half-life of 1,400 years. The isotope with atomic weight 249 has a half-life of 314 days, and was isolated in weighable quantities. [WordNet 1.5]