What Does It Mean?

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From our dictionary:
ple•be•ian

(pli•bE'un), adj.
1. belonging or pertaining to the common people.
2. of, pertaining to, or belonging to the ancient Roman plebs.
3. common, commonplace, or vulgar: a plebeian joke. —adj.
1. a member of the common people.
2. a member of the ancient Roman plebs.