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Synonyms

conclusive

American  
[kuhn-kloo-siv] / kənˈklu sɪv /

adjective

  1. serving to settle or decide a question; decisive; convincing.

    conclusive evidence.

    Synonyms:
    definitive
  2. tending to terminate; closing.


conclusive British  
/ kənˈkluːsɪv /

adjective

  1. putting an end to doubt; decisive; final

  2. approaching or involving an end or conclusion

"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

Other Word Forms

Etymology

Origin of conclusive

1580–90; < Late Latin conclūsīvus, equivalent to Latin conclūs ( us ) (past participle of conclūdere to conclude; see conclusion) + -īvus -ive

Explanation

If you've got a theory that you're trying to prove, and you uncover a conclusive piece of evidence, then the case is closed. Conclusive means you've got your answer, you've proved your theory, and there can't be any doubt about it. If want to prove that frogs can speak, and you record a frog reciting "The Midnight Ride of Paul Revere," that would be conclusive evidence for your claim. But if the frog seemed to be mumbling and mainly making regular old frog noises, critics would say that your video was not conclusive. You can also use the word conclusive to describe winning something easily or by a large margin, like when the talent competition judges handed the tap-dancing bear a conclusive victory, and he moved on triumphantly to the finals.

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Vocabulary lists containing conclusive

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.

See Examples For:

Inspections are “not designed to give you conclusive guidance on the state of the house,” said Deon Marecheau, a member of Thumbtack’s Pro Advisory Board and owner of Antillean Restoration.

From MarketWatch Aug. 15, 2026

“It hurts the hawks more than it hurts the doves,” said Neil Dutta of Renaissance Macro, who assumes that upcoming meetings will be roughly a coin flip because the inflation data won’t be conclusive.

From The Wall Street Journal Aug. 12, 2026

The four received "conclusive grounds" decisions that they were victims between May and July.

From Barron's Aug. 2, 2026

Although the numbers aren't conclusive, it is thought more accidents are happening on privately owned e-scooters.

From BBC Jul. 22, 2026

But they are all too far away and therefore too difficult to observe to provide conclusive evidence of black holes.

From "A Brief History of Time: And Other Essays" by Stephen Hawking

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