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Definition of "perfidious" [per•fid•i•ous]

  • Of, relating to, or marked by perfidy; treacherous. See Synonyms at faithless. (adjective)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Use "perfidious" in a sentence
  • "Then Miriam was furious, and complained to Minna about what she called her perfidious conduct; but Minna only laughed, and told her she could have Petrofsky instead. ""
  • "We wouldn't lie to you about the history of "perfidious" -- even though the word itself suggests deceitfulness."
  • "If soldiers are entitled to deal harshly with wounded enemy soldiers who might be engaged in perfidious acts, surely that entitlement can’t be contingent on holding a mini-trial right there to determine the matter."