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Synonyms

imperious

American  
[im-peer-ee-uhs] / ɪmˈpɪər i əs /

adjective

  1. domineering in a haughty manner; dictatorial; overbearing: an imperious person.

    an imperious manner;

    an imperious person.

    Synonyms:
    arrogant, despotic, tyrannical
    Antonyms:
    submissive
  2. urgent; imperative.

    imperious need.

    Synonyms:
    necessary
    Antonyms:
    unnecessary

imperious British  
/ ɪmˈpɪərɪəs /

adjective

  1. domineering; arrogant; overbearing

  2. rare urgent; imperative

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

  • imperiously adverb
  • imperiousness noun
  • nonimperious adjective
  • nonimperiousness noun
  • unimperious adjective

Etymology

Origin of imperious

First recorded in 1535–45; from Latin imperiōsus “commanding, tyrannical,” equivalent to imperi(um) imperium + -ōsus -ous