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Showing results for doubtful. Search instead for doubtfuln.
Definitions

doubtful

[dout-fuhl] / ˈdaʊt fəl /
ADJECTIVE
questionable, unclear
Synonyms
STRONGEST
debatable dicey dubious hazy indecisive insecure precarious problematic suspicious uncertain undecided uneasy unsettled unstable unsure
WEAK
ambiguous borderline chancy clouded contingent disreputable doubtable dubitable equivocal far-fetched fat chance fishy hazardous iffy impugnable inconclusive indefinite indeterminate indistinct long shot obscure on thin ice open pending shady sneaky speculative suspect touch-and-go touchy unconfirmed up for grabs
Antonyms
STRONGEST
certain clear decided definite determined indubious safe secure settled stable strong sure trustworthy trusty undoubted
WEAK
believing confirmed convinced exact resolved trusting unquestionable
ADJECTIVE
not believing
Synonyms
STRONGEST
dubious hesitant indecisive puzzled skeptical suspicious tentative uncertain unconvinced undecided unsettled unsure
WEAK
agnostic baffled confused discomposed disconcerted distracted distrustful disturbed doubting equivocal faithless faltering flustered hesitating in a quandary in clouds in dilemma irresolute like doubting Thomas lost not following of two minds perplexed questioning theoretical troubled unresolved vacillating wavering without belief
Antonyms
STRONGEST
certain clear decided decisive definite determined secure settled sure trustworthy trusty undoubted
WEAK
believing confident confirmed convinced exact resolved trusting unquestionable

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.

The company is so “heavily embedded” in the modern landscape, he said, and he’s doubtful that will change even as new technologies emerge.

From MarketWatch • Apr. 1, 2026

It is very doubtful that, even if they somehow captured Tehran, Kurds could hold on to power for long.

From Slate • Mar. 6, 2026

“It’s doubtful that the Fed would hike rates to address inflation worries that result from a spike in oil prices,” said Jack Janasiewicz, lead portfolio strategist at Natixis Investment Managers Solutions.

From Barron's • Mar. 3, 2026

Warner remains doubtful that Paramount can ultimately make an offer that surpasses Netflix, people close to the company said.

From The Wall Street Journal • Feb. 17, 2026

She eyed me, a doubtful expression on her face.

From "October Sky" by Homer Hickam

From Roget's 21st Century Thesaurus, Third Edition Copyright © 2013 by the Philip Lief Group.