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.

Definitions of conclusive
  1. adjective
    forming an end or termination; especially putting an end to doubt or question
    conclusive proof”
    “the evidence is conclusive
    definitive, determinate
    supplying or being a final or conclusive settlement
    determining or having the power to determine an outcome
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    not conclusive; not putting an end to doubt or question
    uncertain as a sign or indication
    not leading to a definite ending or result
    head-to-head, neck and neck, nip and tuck
    inconclusive as to outcome; close or just even in a race or comparison or competition
    not final or absolute
    not definitely settling something
    indeterminate, undetermined
    not precisely determined or established; not fixed or known in advance
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Word Family

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