pleb- +

(Latin: common people, common multitude; as opposed to the patricians [upper-class citizens] of Roman times)

pleb (s), plebs (pl) (noun forms)
Primarily a British term for an ordinary person who has low social status: "They think they are too important to waste time on plebs like us."
plebe (s), plebes (pl) (noun forms)
A U.S. informal term for a student, or students, in the first year at a military or naval school.
plebeian (adjective)
1. Typical of someone from a low social class, rather than of someone who is from a higher social class or well educated.

This word is usually used in an insulting way.

2. Of or relating to the common people of ancient Rome; such as, a plebeian magistrate.
3. Of, belonging to, or characteristic of commoners or those who are considered unrefined or coarse in nature or manner; common or vulgar: "Some of these talk show hosts have plebeian tastes or behaviors."
plebeian (s), plebeians (pl) (noun forms)
1. People, the common people, the masses, the lower classes or orders.
2. All of those Roman citizens who were not patricians (upper classes) were plebeians. By the time of Gaius Marius, c. 110 B.C., there were very few politically unimportant posts which remained as strictly the province of the patricians.
3. One of the ordinary citizens of ancient Rome as distinct from the patricians.
4. Someone who behaves in a coarse or crude manner, and has common or vulgar tastes; especially, someone from a lower social class.

Plebiscite is used to mean a vote by a whole electorate to decide a question of importance; a referendum; a public expression of the will or opinion of a whole community.

In history, a law enacted by the plebs or ordinary citizens of ancient Rome gathered in assembly. Also as an adjective: plebiscitary

plebeianism (noun)
The state, conduct, manners, or quality of being plebeian; vulgarity, that is, lacking taste and refinement.
plebian, an alternative spelling of plebeian
1. Belonging to, or pertaining to, the common people.
2. A reference to, or belonging to, the ancient Roman plebs.
3. Common, commonplace, or vulgar; such as, a plebian or a plebeian joke.
plebicolar (adjective)
A person who courts the favor of the common people.
plebicolist (s), plebicolists (pl) (noun forms)
1. Someone who flatters, or courts the favor of, the common people; a demagogue.
2. Giving the appearance of being a friend of the people; an orator who appeals to the passions and prejudices of his audience.
plebieanize, plebieanizes, plebieanized, plebieanizing (verb forms)
To render plebeian; that is, common or vulgar (without courtesy and manners).
plebification
The act of making plebeian or common; the act of vulgarizing or making something which is little known or difficult to understand more widely known or popular among the public; to popularize.
plebiocologist
Someone who who flatters the common people in order to get them to follow his or her viewpoints and to get the people to take action in accordance with what is being promoted.
plebiocology (s), plebiocologies (pl) (noun forms)
1. The study of ordinary people and their common behaviors, desires, political leanings, etc.
2. Learning about the trends of the general public for food preferences, clothing styles, TV interests, social networking, and other interests.
plebiscitarian (s), plebiscitarians (pl) (noun forms)
An advocate of a plebiscite or a vote by the electorate to determine public opinion about a question of national importance.
plebiscitary (adjective)
A reference to, pertaining to, or of the nature of a plebiscite; that is, a vote by the electorate determining public opinion on a question of national importance.
plebiscite (s), plebisites (pl) (noun forms)
1. A vote in which a population exercises the right of national self-determination: "They are going to hold a plebiscite on the question of national independence."
2. A public expression of the will or opinion of a whole community: "The issues will be decided by plebiscites."
3. A direct vote in which the entire electorate is invited to accept or to refuse a proposal: "The amendment to the constitution was ratified in a plebiscite."