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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

Etymology

Origin of doubtful

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

Explanation

When you're doubtful about something, you're not sure about it. You might feel doubtful about the picnic you've planned if the forecast calls for torrential rain. Whether you're uncertain, undecided, or suspicious, you can describe yourself as doubtful. You'll be doubtful about your taxi driver's sense of direction when you pass the same building for the third time. You might also be doubtful about whether or not to try skydiving. Doubtful means "full of doubt," and doubt is from the Old French doter, "doubt or be afraid," with a Latin root, dubitare, "to question, hesitate, or waver in opinion."

Keep Reading on Vocabulary.com

Vocabulary lists containing doubtful

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.

“So it was good news. You know, I’m sure it’s painful. Doubtful, day to day, whatever — I’m just happy there wasn’t anything torn.”

From Los Angeles Times • Nov. 10, 2022

Can anyone ever outdo Carl Anderson’s 1973 version of “Heaven on Their Minds,” one of the most beloved songs from “Jesus Christ Superstar”? Doubtful, but we can enjoy the attempts and tributes.

From Seattle Times • Sep. 13, 2021

In 1958, right after “The Doubtful Guest,” came “The Object-Lesson.”

From The New Yorker • Dec. 3, 2018

Doubtful the credit card companies will act on their own goodwill.

From New York Times • Feb. 19, 2018

"Doubtful that!" said Edward, with a downward glance at his own stout limbs.

From Elsie's Widowhood A Sequel to Elsie's Children by Finley, Martha