de·ci·sive/dɪ`saɪsɪv; dɪˈsaɪsɪv/ adj 1 having an important effect on the result of something 重要的，关键的: a decisive moment in his career 他事业中的一个关键时刻 2 good at making decisions quickly and firmly 果断的，有决断力的: a strong, decisive leader 坚强的、有决断力的领导者 3 a decisive victory, result etc is very definite and clear 〔胜利、结果等〕明确的，显然的: The US team won a decisive victory. 美国队大胜了一仗。