DUBIOUS Synonyms: 142 Similar and Opposite Words

Q: 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

Q: 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

Q: 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

Q: 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

dubious

adjective

ˈdü-bē-əs

Definition of dubious next

as in questionable

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

Synonyms & Similar Words

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Antonyms & Near Antonyms

as in reluctant

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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Antonyms & Near Antonyms

as in unlikely

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

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Antonyms & Near Antonyms

as in skeptical

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

Synonyms & Similar Words

Antonyms & Near Antonyms

Synonym Chooser

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

Example Sentences

Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.

Recent Examples of dubious Getting there, however, is a more dubious matter. —

Sara Holdren, Vulture, 17 Mar. 2026 Which of those experiments — whether in humans, mice, or cells — have more dubious or more reliable conditions and statistical analyses? —

Brittany Trang, STAT, 17 Mar. 2026 Never mind the dubious media contracts, the luxury jet, and the presence of Corey Lewandowski, a shadow secretary rumored to be in a romance with Noem that both deny. —

Nick Miroff, The Atlantic, 13 Mar. 2026 The logic of the incentive program is dubious, as is the timing of the measure. —

Adam Summers, San Diego Union-Tribune, 11 Mar. 2026 See All Example Sentences for dubious

Recent Examples of Synonyms for dubious

Adjective

Saturday, further uncertainty entered the equation, with guard Norman Powell listed as questionable due to calf tightness, having recently missed seven consecutive games due to a groin strain.

— Ira Winderman, Sun Sentinel, 21 Mar. 2026
He was previously listed as questionable to play on the team’s injury report.

— Daily News, Daily News, 21 Mar. 2026