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Synonyms

dubious

American  
[doo-bee-uhs, dyoo-] / ˈdu bi əs, ˈdju- /

adjective

  1. doubtful; marked by or occasioning doubt.

    a dubious reply.

    Synonyms:
    unclear, obscure, ambiguous, equivocal
  2. of doubtful quality or propriety; questionable.

    a dubious compliment; a dubious transaction.

  3. of uncertain outcome.

    in dubious battle.

  4. wavering or hesitating in opinion; inclined to doubt.

    Synonyms:
    hesitant, uncertain, undecided

dubious British  
/ ˈdjuːbɪəs /

adjective

  1. marked by or causing doubt

    a dubious reply

  2. unsettled in mind; uncertain; doubtful

  3. of doubtful quality; untrustworthy

    a dubious reputation

  4. not certain in outcome

"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

Synonym Usage

See doubtful.

Other Word Forms

Etymology

Origin of dubious

First recorded in 1540–50; from Latin dubius; cf. doubt ( def. )

Explanation

Choose the adjective dubious for something you have doubts about or you suspect is not true. That bridge you just "bought" might be of dubious value. Dubious stems from Latin dubiosus, "doubtful" or "uncertain," and contains the Latin root duo in this case meaning "of two minds." This is apparent in that dubious generally describes something that appears one way but is truly another. A dubious claim is probably not true, whereas a dubious website or character is of questionable quality. Dubious can also be synonymous with doubtful, as in "she was dubious about the idea."

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Vocabulary lists containing dubious

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.

After decades of ceremonial nods from Congress and statehouses across the country, Juneteenth then got its biggest, albeit most dubious, boost.

From Salon • Jun. 19, 2026

A 1949 government audit found that two-thirds of the schools had dubious accounting.

From MarketWatch • Jun. 18, 2026

Honestly, I’m dubious of the film’s certainty that folks even have the bandwidth to care about such news, let alone agree on what they’re seeing.

From Los Angeles Times • Jun. 10, 2026

The new contracts for two ageing stars suddenly look very dubious – but this is easy to say now.

From BBC • May 30, 2026

Aunt Melissa gives me a dubious look but returns to her walnuts.

From "South of Somewhere" by Kalena Miller

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