an agitator who makes use of popular prejudices in order to gain power
a leader of the common people in ancient times
demagogic /-ʹgogik, -ʹgojik/ adj
demagoguery /-gəri/ noun
demagogy /-gi, -ji/ noun
[Greek dēmagōgos, from dēmos people + agōgos leading, from agein to lead]