Plebeian (adjective)

1. Belonging to or characteristic of the common people.
2. Coarse or vulgar.

Origin:

From latin plebeius (of or belonging to the plebs).

Examples:

1. The decor in this restaurant is quite plebeian, with plastic chairs and paper napkins.
2. She was embarrassed by her plebeian upbringing when she moved to the upper-class neighborhood.
3. The actor's plebeian mannerisms made him popular with working-class audiences.
4. The aristocrats looked down on the plebeian fashion of the day.
5. The plebeian nature of the event was evident in the simple decorations and casual dress code.