unnilseptium
un·nil·sep·tium
noun
1.
a transuranic element that has not been found in nature
Origin
Systematic element name, from un- + nil- + sept- + -ium.
Related words
Broader terms
WordNet 2.1 (Princeton University). Wiktionary (CC BY-SA). WordNet 2.1 Copyright Princeton University. All rights reserved. Wiktionary content is available under the Creative Commons Attribution-ShareAlike Licence.