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Definitions

questionable

[kwes-chuh-nuh-buhl] / ˈkwɛs tʃə nə bəl /
ADJECTIVE
doubtful, uncertain
Synonyms
STRONGEST
ambiguous arguable controversial debatable dubious problematic suspicious unproven vague
WEAK
apocryphal contingent controvertible cryptic disputable dubitable enigmatic equivocal fishy hard to believe hypothetical iffy indecisive indefinite indeterminate moot mysterious obscure occult open to doubt open to question oracular paradoxical problematical provisional shady suspect unconfirmed undefined under advisement under examination unreliable unsettled
Antonyms
STRONGEST
certain clear definite incontrovertible indubious sure trustworthy trusty undoubted unquestionable
WEAK
indisputable proven

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.

With so much questionable financial behavior going largely unpunished, is it any wonder that everyone seems to want to hit the jackpot—against ridiculously long odds—in prediction markets?

From The Wall Street Journal • May 5, 2026

But it also means that an increasing amount of questionable science is slipping through an overworked peer review process.

From Slate • May 3, 2026

Reaves was upgraded to questionable Thursday, a surprising three-week progression from when he was grabbing at his left upper side in the first half of a game against Oklahoma City on April 2.

From Los Angeles Times • Apr. 24, 2026

Investors who see problems in private credit and questionable valuations in the stock market could relocate assets to the Treasury market as it reaches the right price.

From Barron's • Apr. 22, 2026

There’s no map, but he does pull out a questionable sandwich-size Ziploc bag.

From "Dry" by Neal Shusterman and Jarrod Shusterman

Vocabulary lists containing questionable

"The Tragedy of Hamlet," Vocabulary from Act 1

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