plebiscitum

noun2

1. •
   A law enacted by the plebs, under the superintendence of a tribune or some subordinate plebeian magistrate, without the senate's intervention.

   • Still worse went it with another individual; doomed, by extempore Plebiscitum, to the Lanterne; […] — 1837
2. •
   Synonym of plebiscite (“a direct popular vote on an issue of public importance, such as an amendment to the constitution, a change in the sovereignty of the nation, or some government policy; a referendum”).

   • The propositions of M[axime] du Camp are as follows: […] 3. No war to be declared before it has been submitted to a plebiscitum of the nations preparing to take part in it. — 1894