1.(火箭,核弹等准备发射,爆炸时的)时间计算(阶段);(火箭,核弹发射,爆炸前)计时系统
2.(雷达的)回答脉冲比;(电视的)脉冲分频[脱漏]
3.读数,示度;计数损失[漏失]
1.the counting of numbers backward, for example from ten to zero, before something important happens
2.the period of time just before an important event
1.Countdowns are an integral part of the theatre, even though the clock seems to spend as much time stopped as it does ticking towards zero.
倒计时是电影院不可或缺的一部分，即使时钟要花费同指针滴答滴答趋向零相同的时间就会停止。
2.George (Capital) is considered to be one of the finest beaches in the world, and often appears in countdowns of the world's top 10 beaches.
位于首都圣乔治岛三千米长的安塞海滩是世界上最好的海滩之一，经常出现在世界最佳海滩的前十名当中。
3.But of course that's all nonsense. Being 23 has nothing to do with life expectancies or countdowns or year-day-hour-minute conversions.
当然了，这样说很荒谬，23岁和平均寿命、生命倒计时、年-天-小时-分钟的换算关系扯不上关系。