I believe he’s referring to element 117, Ununseptium. The International Union of Pure and Applied Chemistry, the IUPAC, created rules for temporary names as placeholders in the periodic table of elements for as yet undiscovered elements. Wikipedia (http://en.wikipedia.org/wiki/Systematic_element_name) has an article on this Systemic Element Name. Briefly, it’s based on the atomic number of the element, in this case 117, so its name consists of the syllables “un” (one), “un” (one) and “sept” (7) for 117 plus the suffix “ium” which designates a a transuranic element, an element with an atomic number greater than 92, the element Uranium.

I can just see the next Star Trek movie: “Star Trek Ununennium — The Undiscovered Element.”

The discoverers of the new element have the right select a permanent name for the new element, but there have been controveries. See Wikipedia (http://en.wikipedia.org/wiki/Element_naming_controversy).