decisive

Universal Words adjective 1 very important for the final result of a particular situation: a decisive factor / victory / battle * Climate was a decisive factor in establishing where the tournament should be held. * She has played a decisive role in the peace negotiations. * a decisive step (= an important action that will change a situation) towards a cleaner environment 2 able to decide sth quickly and with confidence: decisive management * The government must take decisive action on gun control. compareINDECISIVE decisively adverb: She shook her head decisively.