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What is the opposite of “indubitable”?

What is the antonym of “indubitable”?

The antonyms of indubitable are doubtful, questionable, and uncertain. These words convey a sense of doubt or lack of certainty.

Brief Definitions of the Antonym(s)

Learn when and how to use these words with these examples!


Not feeling certain or confident about something; uncertain.


He was doubtful about the success of his plan and decided to seek advice from his colleagues.


Open to doubt or suspicion; not reliable or trustworthy.


The company's financial records were questionable, and the investors demanded an audit.


Not able to be relied on; not known or definite.


The weather forecast was uncertain, and the organizers of the outdoor event had to make contingency plans.

How are these antonyms different from each other?

  • 1Doubtful implies a lack of confidence or certainty, while questionable suggests that something is unreliable or untrustworthy.
  • 2Uncertain describes something that is not definite or reliable, but it does not necessarily imply suspicion or doubt.

Good things to know

  • 1Express Doubt: Use doubtful, questionable, and uncertain to express uncertainty or doubt in conversations.
  • 2Evaluate Information: Incorporate these antonyms when evaluating information to identify potential biases or inaccuracies.
  • 3Enhance Writing: Utilize these antonyms in writing to create suspense or convey a sense of ambiguity.

Remember this!

The antonyms of indubitable convey a sense of doubt or lack of certainty. Doubtful implies a lack of confidence, questionable suggests unreliability, and uncertain describes something that is not definite. Use these words to express doubt, evaluate information, and enhance writing by creating suspense or conveying ambiguity.

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