10 June 2016
Element 117 received the name tennessine by the International Union of Pure and Applied Chemistry (IUPAC) in June 2016. Tennessine has the symbol Ts. The element is named for the state of Tennessee, home of the Oak Ridge National Laboratory and Vanderbilt University. The element was discovered in by a collaborative effort involving researchers at Oak Ridge, Vanderbilt, the Joint Institute for Nuclear Research in Dubna, Russia, and the Lawrence Livermore National Laboratory in California.
New IUPAC guidelines formulated in 2016 require new elements be named after either a mythological character or concept (or an astronomical object named after such a mythological concept), a mineral, a place, or a scientist. Elements in columns 1–16 of the periodic table take the usual suffix -ium. Those in column 17 take the suffix -ine, and those in column 18 the suffix -on. Tennessine is in column 17, hence the -ine ending. Of course, older names for elements may not conform to these guidelines.
Source: “IUPAC is Naming the Four New Elements Nihonium, Moscovium, Tennessine, and Oganesson.” IUPAC press release. 8 June 2016.