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Synonyms

doubtful

American  
[dout-fuhl] / ˈdaʊt fəl /

adjective

  1. of uncertain outcome or result.

    Synonyms:
    problematic, dubious, indecisive, unsettled, undetermined
    Antonyms:
    certain
  2. admitting of or causing doubt; uncertain; ambiguous.

    Synonyms:
    indeterminate, unsure
    Antonyms:
    certain
  3. unsettled in opinion or belief; undecided; hesitating.

    Synonyms:
    hesitant, vacillating, irresolute
  4. of equivocal or questionable character.

    His tactics are highly doubtful.

    Synonyms:
    shady

doubtful British  
/ ˈdaʊtfʊl /

adjective

  1. unlikely; improbable

  2. characterized by or causing doubt; uncertain

    a doubtful answer

  3. unsettled; unresolved

  4. of questionable reputation or morality

  5. having reservations or misgivings

  6. (of a sportsperson) not likely to be fit enough to play or take part

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

noun

  1. a person who is undecided or uncertain about an issue

  2. a sportsperson who is not likely to be fit enough to play or take part

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Usage

See doubt.

It was formerly considered correct to use whether after doubtful (it is doubtful whether he will come), but now if and that are also acceptable

Related Words

Doubtful, dubious, incredulous, skeptical imply reluctance or unwillingness to be convinced. To be doubtful about something is to feel that it is open to question or that more evidence is needed to prove it: to be doubtful about the statements of witnesses. Dubious implies vacillation, unsureness, or suspicion: dubious about suggested methods of manufacture. Incredulous means unwilling or reluctant to believe: incredulous at the good news. Skeptical implies a general disposition to doubt or question: skeptical of human progress.

Other Word Forms

  • doubtfully adverb
  • doubtfulness noun
  • predoubtful adjective
  • predoubtfully adverb
  • quasi-doubtful adjective
  • quasi-doubtfully adverb
  • undoubtful adjective
  • undoubtfully adverb
  • undoubtfulness noun

Etymology

Origin of doubtful

First recorded in 1350–1400, doubtful is from the Middle English word douteful. See doubt, -ful

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.

It’s possible that alternative investments other than hedge funds have done significantly better, but this seems doubtful.

From MarketWatch

With consumer confidence still very low, Saunders says he remains doubtful that overall consumer spending growth is set to accelerate strongly.

From The Wall Street Journal

And even if a transition occurred, the durability of any new investment regime would be doubtful.

From Barron's

There is also strong support at 6,500, and it appeared that might come into play with the break below 6,800, but that is doubtful now.

From MarketWatch

Gary Klein’s pick: It seems doubtful that Rams receiver Davante Adams will heal sufficiently from a hamstring injury to play in cold and possible rainy conditions.

From Los Angeles Times