oppressor

from WordNet (r) 3.0 (2006)
oppressor
    n 1: a person of authority who subjects others to undue
         pressures
    
from The Collaborative International Dictionary of English v.0.48
Oppressor \Op*press"or\, n. [L.]
   One who oppresses; one who imposes unjust burdens on others;
   one who harasses others with unjust laws or unreasonable
   severity.
   [1913 Webster]

         The orphan pines while the oppressor feeds. --Shak.
   [1913 Webster]

         To relieve the oppressed and to punish the oppressor.
                                                  --Swift.
   [1913 Webster]
    
from Moby Thesaurus II by Grady Ward, 1.0
34 Moby Thesaurus words for "oppressor":
      Simon Legree, absolute monarch, absolute ruler, all-powerful ruler,
      arrogator, autarch, autocrat, bully, caesar, commissar, czar,
      despot, dictator, disciplinarian, driver, duce, hard master,
      intimidator, iron hand, martinet, oligarch, overlord, persecutor,
      pharaoh, scourge, slave driver, stickler, strong man, taskmaster,
      tormentor, torturer, tyrant, usurper, warlord

    

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