Synonyms of dubious

dubious

adjective

ˈdü-bē-əs 

1

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

• questionable
• disputable
• suspicious
• doubtful
• problematic
• debatable
• suspect
• shaky
• ambiguous
• fishy
• alleged
• equivocal
• dodgy
• shady
• queer
• unclear
• dubitable
• doubtable
• unlikely
• uncertain
• weak
• moot
• supposed
• improbable
• undetermined
• flimsy
• so-called
• undecided
• far-fetched
• open

Antonyms & Near Antonyms

• certain
• indisputable
• unquestionable
• sure
• undeniable
• undoubted
• indubitable
• incontestable
• unproblematic
• decisive
• definitive
• obvious
• questionless
• positive
• hands-down
• clear
• open-and-shut

2

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

Synonyms & Similar Words

• reluctant
• hesitant
• unsure
• unwilling
• skeptical
• loath
• uncertain
• cagey
• doubtful
• disinclined
• reticent
• indisposed
• unenthusiastic
• ambivalent
• questioning
• timid
• averse
• conflicted
• wobbly
• faltering
• irresolute
• infirm
• indecisive
• undecided
• vacillating
• halting
• uneager
• shy
• fainthearted

Antonyms & Near Antonyms

• enthusiastic
• eager
• inclined
• happy
• glad
• keen
• certain
• willing
• ready
• disposed
• decided
• sure
• determined
• resolute
• unquestioning

3

as in unlikely

not likely to be true or to occur

made the dubious claim of being of royal blood

Synonyms & Similar Words

• unlikely
• questionable
• doubtful
• improbable
• odd
• flimsy
• bizarre
• far-fetched
• impossible
• incredible
• implausible
• unapt
• ridiculous
• unbelievable
• inconceivable
• absurd
• unimaginable
• unthinkable
• fantastic
• nonsensical
• foolish
• outlandish
• preposterous
• insane
• unreal
• crazy
• slight
• outside
• remote
• wild

Antonyms & Near Antonyms

• probable
• likely
• plausible
• possible
• credible
• potential
• conceivable
• earthly
• believable
• imaginable
• liable

4

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

• skeptical
• unsure
• suspicious
• uncertain
• doubtful
• unsettled
• unconvinced
• distrustful
• mistrustful
• undecided
• ambivalent
• on the fence
• hesitant
• trustless
• hinky
• conflicted
• equivocal
• diffident
• insecure
• irresolute
• indecisive
• halting
• vacillating
• wavering

Antonyms & Near Antonyms

• certain
• positive
• sure
• convinced
• confident
• assured
• sanguine
• decisive
• determined
• resolute
• self-assured

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

Recent Examples of dubious

In multiple lawsuits that are now combined, Nutex investors accuse the company of hiding its partnership with HaloMD and say the dubious arrangement exposes the company to further legal risks. — Tara Bannow, STAT, 29 June 2026

Pima County Sheriff Chris Nanos is dubious of a new demand letter in the Nancy Guthrie case received by TMZ on Friday. — Marina Watts, Entertainment Weekly, 29 June 2026

Kovel is not alone in finding this highly dubious. — Jon Wertheim, CBS News, 28 June 2026

The actual economics of AI automation, meanwhile, remain pretty dubious. — Frank Landymore, Futurism, 25 June 2026

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