hoi polloi

from Dictionary.com/Word of the Day:

hoi polloi \hoi-puh-LOI\, noun:
The common people generally; the masses.

Hoi polloi is Greek for "the many."

Usage: Some argue that the definite article ("the") should not be used in front of "hoi polloi," as hoi means "the" in Greek. However, "the hoi polloi" has been used since the earliest recorded instances of the term in English and is considered correct by most authorities.