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 Even at the height of his fame, there were dubious aspects of his personal life — often self-seeded to sustain his enigma — that poked hellified holes in his impermeability as an entertainer. —

Rodney Carmichael, NPR, 3 June 2026 Governor Gretchen Whitmer, often touted as a viable Democratic presidential nominee, has always offered a helping hand to major corporations, even when the benefits to her constituents are dubious. —

Andrew Cockburn, Harpers Magazine, 2 June 2026 After the war, Krick, who launched a dubious cloud seeding venture, claimed the Americans had made the successful forecast. —

Andrea Thompson, Scientific American, 29 May 2026 Keeping Kim and losing Espinal to a DFA earlier this week looked dubious when Hernandez went down with another injury on Tuesday. —

Doug Padilla, Oc Register, 28 May 2026 See All Example Sentences for dubious

Recent Examples of Synonyms for dubious

Adjective

The 27-year-old is known for his steadying presence and reliable defense in the midfield, and with questionable depth behind him, losing Adams to an injury or yellow card suspension could prove disastrous.

— Zack Cox, Boston Herald, 7 June 2026
Using a specific set of situational conditions under which the detection system is effective is questionable, Chris Smith, one of the plaintiff’s attorneys, told Ars.

— Cyrus Farivar, ArsTechnica, 7 June 2026