nomen nudum
noun
no·men nu·dum ˈnō-mən-ˈnü-dəm 
-ˈnyü-
plural nomina nuda ˈnä-mə-nə-ˈnü-də
-ˈnyü-,
ˈnō-
: a proposed taxonomic name that is invalid because the group designated is not described or illustrated sufficiently for recognition, that has no nomenclatural status, and that consequently can be used as though never previously proposed
Word History
Etymology
New Latin, bare name
First Known Use
1881, in the meaning defined above