conclusive applies to reasoning or logical proof that puts an end to debate or questioning.
conclusive evidence
decisive may apply to something that ends a controversy, a contest, or any uncertainty.
a decisive battle
determinative adds an implication of giving a fixed character or direction.
the determinative factor in the court's decision
definitive applies to what is put forth as final and permanent.
the definitive biography
Example Sentences
You must be decisive and persistent to succeed in this competitive field. I stood there wondering what to do, but my sister was more decisive and immediately went to the phone. The fight ended with a decisive blow. the decisive battle of the war The poverty of his childhood played a decisive role in his adult life. The meeting is seen as a decisive step toward a peace treaty. See More
Recent Examples on the WebPhysicians may differ on when a situation becomes life-threatening, or hesitate to take decisive action if a quick decision places them into some legal gray area. Grace Segers, The New Republic, 14 Sep. 2022 Ukrainian forces kept up their surge in the country's east Saturday after punching through Russian defenses in a surprise counteroffensive that could prove a decisive turning point in the war. Phil Mccausland, NBC News, 10 Sep. 2022 An individual who cannot take decisive action in the face of multiple priorities can leave an organization paralyzed. Expert Panel, Forbes, 8 Aug. 2022 New Lake County sustainability manager Robin Grooms believes now is the time to take decisive action to protect and invest in a healthy environment. Gavin Good, Chicago Tribune, 4 Aug. 2022 By precipitating Beijing’s overreaction, Pelosi has created a new opportunity for Taiwan’s friends to take decisive action against the CCP. The Editors, National Review, 3 Aug. 2022 But lost in the recriminations and finger-pointing is the other side of the aisle: All 50 Republicans in the Senate have been as opposed to decisive action to confront planetary warming.New York Times, 20 July 2022 In 2018, Francesco Molinari became the first European, and second player overall in the competition’s current format, to go 5-0 at a Ryder Cup by clinching the decisive point over Phil Mickelson. Andrew Dampf, ajc, 30 May 2022 But scoring bursts go both ways, and Canada’s subsequent three goals proved to be the decisive point in the game. David Wharton, Los Angeles Times, 8 Feb. 2022 See More