Haranguer

from WordNet (r) 3.0 (2006)

haranguer
    n 1: a public speaker who delivers a loud or forceful or angry
         speech

from The Collaborative International Dictionary of English v.0.48

Haranguer \Ha*rang"uer\ (h[.a]*r[a^]ng"[~e]r), n.
   One who harangues, or is fond of haranguing; a declaimer.
   [1913 Webster]

         With them join'd all th' haranguers of the throng,
         That thought to get preferment by the tongue. --Dryden.
   [1913 Webster]