Synonyms & Antonyms of dubious

1 giving good reason for being doubted, questioned, or challenged
  • any letter bearing the signature of Geronimo would be of dubious authenticity, to say the least

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2 slow to begin or proceed with a course of action because of doubts or uncertainty
  • I'm dubious about our plan to go hang gliding without having had any training

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3 not likely to be true or to occur
  • made the dubious claim of being of royal blood

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4 not feeling sure about the truth, wisdom, or trustworthiness of someone or something
  • dubious about a diet that claims I can eat all I want and still lose weight

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See the Dictionary Definition 

Frequently Asked Questions About dubious

How does the adjective dubious contrast with its synonyms?

Some common synonyms of dubious are doubtful, problematic, and questionable. While all these words mean "not affording assurance of the worth, soundness, or certainty of something," dubious stresses suspicion, mistrust, or hesitation.

dubious about the practicality of the scheme

When would doubtful be a good substitute for dubious?

The meanings of doubtful and dubious largely overlap; however, doubtful implies little more than a lack of conviction or certainty.

doubtful about whether I said the right thing

Where would problematic be a reasonable alternative to dubious?

While in some cases nearly identical to dubious, problematic applies especially to things whose existence, meaning, fulfillment, or realization is highly uncertain.

whether the project will ever be finished is problematic

When could questionable be used to replace dubious?

The words questionable and dubious can be used in similar contexts, but questionable may imply no more than the existence of doubt but usually suggests that the suspicions are well-grounded.

a man of questionable honesty

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Time Traveler for dubious

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The first known use of dubious was in 1548

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Cite this Entry

“Dubious.” Thesaurus, Merriam-Webster, Accessed 21 Jan. 2021.

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More from Merriam-Webster on dubious

Dictionary: Definition of dubious

Nglish: Translation of dubious for Spanish Speakers

Britannica English: Translation of dubious for Arabic Speakers

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