bohrium

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. An artificially produced radioactive element with atomic number 107 whose most long-lived isotopes have mass numbers of 261, 262, and 264 with half-lives of 11.8 milliseconds, 0.1 second, and 0.44 second, respectively. Also called unnilseptium. See Table at element.

Wiktionary

1. n. A transuranic chemical element (symbol Bh) with an atomic number of 107.

WordNet 3.0

1. n. a transuranic element