conclusive
Americanadjective
-
serving to settle or decide a question; decisive; convincing.
conclusive evidence.
- Synonyms:
- definitive
-
tending to terminate; closing.
adjective
-
putting an end to doubt; decisive; final
-
approaching or involving an end or conclusion
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.
Vocabulary lists containing conclusive
The Emancipation Proclamation (1862)
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Case Closed: Clud, Clus
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The Articles of Confederation (1777)
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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.
But the internal research it conducted was conclusive.
From The Wall Street Journal • May 16, 2026
He declared himself "no longer sceptical" about the issue, having waited for conclusive proof that humanity was changing the climate.
From Barron's • May 6, 2026
They may be able to say there were “insufficient funds” or “suspected fraud” rather than give you a conclusive answer.
From MarketWatch • Apr. 27, 2026
As in the less conclusive first season, it feels engineered to deliver the characters to happy, or relatively happy, endings, and to send viewers out not regretting their investment of time.
From Los Angeles Times • Apr. 16, 2026
“The sign of the Deathly Hallows on Ignotus’s grave is conclusive proof!”
From "Harry Potter and the Deathly Hallows" by J.K. Rowling
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
