ple·be·ian / pliˈbēən/ • n. (in ancient Rome) a commoner. ∎  a member of the lower social classes.• adj. of or belonging to the commoners of ancient Rome. ∎  of or belonging to the lower social classes. ∎  lacking in refinement: he is a man of plebeian tastes.

plebeian pert. to, a member of, the Roman plebs XVI; of low birth or rank XVII. f. L. plēbēius, f. plēbs, plēb- commonalty of ancient Rome, perh. rel. to plēnus FULL, Gr. plêthos, plēthús multitude; see -AN.
So plebiscite law enacted by the plebs XVI; direct vote of the whole electorate XIX. — (O)F. plébiscite — L. plēbiscītum, f. plēbs, plēb- + scītum ordinance, sb. use of n. pp. of sciscere approve, vote for, rel. to scīre know.

plebeian General body of Roman citizens, as distinct from the small patrician class. In the early years of the Republic, they were barred from public office and from marrying a patrician. The gulf between the two classes gradually closed. By the 3rd century bc, there was little legal distinction between them, although social differences remained.

plebeian (in ancient Rome) a commoner, as opposed to the patricians, senators, and knights. Recorded from the mid 16th century, the word comes from Latin plebs, pleb- ‘the common people’.