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Synonyms

nefarious

American  
[ni-fair-ee-uhs] / nɪˈfɛər i əs /

adjective

  1. extremely wicked or villainous; iniquitous.

    a nefarious plot.

    Synonyms:
    execrable, atrocious, vile, infamous, heinous, flagitious
    Antonyms:
    honest, good

nefarious British  
/ nɪˈfɛərɪəs /

adjective

  1. evil; wicked; sinful

"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

  • nefariously adverb
  • nefariousness noun
  • unnefarious adjective
  • unnefariously adverb
  • unnefariousness noun

Etymology

Origin of nefarious

First recorded in 1595–1605; from Latin nefārius “wicked, vile,” equivalent to nefās “offense against divine or moral law” (from ne-, negative prefix + fās “law, right”) + -ius -ious

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Let him know that there’s a chance this is a romance scam/honey trap and that even the smartest people get hoodwinked by nefarious characters who take advantage of their loneliness.

From MarketWatch

Related: ‘Could a nefarious caregiver steal her money?’

From MarketWatch

What measures are you proactively taking to ensure your personal data isn’t used for nefarious means?

From Salon

Web tracking, aside from having nefarious connotations, can drain your device of battery — but with this tool, you can browse up to 44% faster, use up to 39% less bandwidth and greatly improve battery life.

From Salon

And you may or may not have been given my number as part of my ex-friend’s nefarious revenge plot.

From Literature