determining or having the power to determine an outcome; "cast the decisive vote"; "two factors had a decisive influence" characterized by decision and firmness; "an able an decisive young woman"; "we needed decisive leadership"; "she gave him a decisive answer" unmistakable; "had a decisive lead in the polls
If a fact, action, or event is decisive, it makes it certain that there will be a particular result. his decisive victory in the presidential elections + decisively de·ci·sive·ly The plan was decisively rejected by Congress three weeks ago
If someone is decisive, they have or show an ability to make quick decisions in a difficult or complicated situation. He should give way to a younger, more decisive leader. + decisively de·ci·sive·ly `I'll call for you at half ten,' she said decisively. + decisiveness de·ci·sive·ness His supporters admire his decisiveness