[1] : The Collaborative International Dictionary of English v.0.48

arrogant \ar"rogant\, a. f. arrogant, l. arrogans, p. pr. of
   arrogare. see arrogate.
   1. making, or having the disposition to make, exorbitant
      claims of rank or estimation; giving one's self an undue
      degree of importance; assuming; haughty; -- applied to
      persons.
      1913 webster

            arrogant winchester, that haughty prelate. --shak.
      1913 webster

   2. containing arrogance; marked with arrogance; proceeding
      from undue claims or self-importance; -- applied to
      things; as, arrogant pretensions or behavior.
      1913 webster

   syn: magisterial; lordly; proud; assuming; overbearing;
        presumptuous; haughty. see magisterial.
        1913 webster
see also:
arrogate magisterial 

[2] : WordNet (r) 2.0

arrogant
     adj : having or showing feelings of unwarranted importance out of
           overbearing pride; "an arrogant official"; "arrogant
           claims"; "chesty as a peacock" syn: chesty, self-important
see also:
chesty self-important 

[3] : Moby Thesaurus II by Grady Ward, 1.0

145 moby thesaurus words for "arrogant":
   absolute, absolutist, absolutistic, affected, arbitrary,
   aristocratic, artificial, assuming, assured, audacious,
   authoritarian, authoritative, autocratic, big, bloated, boastful,
   bold, bossy, brash, brassy, brazen, bumptious, cavalier,
   challenging, cheeky, clannish, cliquish, cocksure, cocky, cold,
   conceited, condescending, confident, contemptuous, contumelious,
   convinced, cool, daring, decided, defiant, defying, derisive,
   despotic, determined, dictatorial, disdainful, disregardful,
   domineering, egotistical, exclusive, familiar, feudal, forward,
   greatly daring, grinding, haughty, high and mighty,
   high-and-mighty, high-faluting, high-flown, high-handed,
   high-headed, high-nosed, highfalutin, hoity-toity, hubristic,
   imperative, imperial, imperious, impertinent, important, impudent,
   insolent, insulting, lofty, lordly, magisterial, magistral,
   mannered, masterful, monocratic, obtrusive, oppressive,
   overbearing, overconfident, overpresumptuous, overruling, oversure,
   overweening, patronizing, peremptory, persuaded, pert, poised,
   pompous, pontifical, positive, presuming, presumptuous, procacious,
   proud, puffy, purse-proud, pushy, reassured,
   regardless of consequences, repressive, saucy, scornful, secure,
   self-assertive, self-assured, self-confident, self-important,
   self-reliant, severe, showy, sneering, sniffy, snobbish, snobby,
   snooty, snotty, strict, stuck-up, stuffy, supercilious, superior,
   suppressive, sure, swaggering, toploftical, toplofty, tyrannical,
   tyrannous, unafraid, undoubting, unfaltering, unhesitating,
   unwavering, uppish, uppity, upstage, vain, withering

Arrogant >> A Words
Arrogant, definition of term: Arrogant
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