[yoo-nil-sep-tee-uh
m] 
| Chemistry, Physics. provisional name for the transuranic element with atomic number 107. Symbol: Uns |
| bohr·i·um (bôr'ē-əm, bōr'-) n. Symbol Bh 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. [After Niels Henrik David Bohr.] |
| un·nil·sep·ti·um (yōō'nĭl-sěp'tē-əm) n. See bohrium. [Latin ūnus, one; see union + Latin nīl, nothing; see nil + Latin septem, seven; see septet + -ium.] |
unnilseptium
a synthetic element in Group VIIb of the periodic table. It is thought to be chemically similar to the rare metal rhenium.
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