From The Collaborative International Dictionary of English v.0.48 [gcide]:
Demagogue \Dem"a*gogue\ (?; 115), noun [Gr. dhmagwgo's a popular leader; commonly in a bad sense, a leader of the mob; dh^mos the people + 'agwgo's leading, fr. 'a'gein to lead; akin to E. act: cf. F. d['e]magogue.] A leader of the rabble; one who attempts to control the multitude by specious or deceitful arts; an unprincipled and factious mob orator or political leader.
From WordNet (r) 3.0 (2006) [wn]:
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