trump card

英 [ˈtrʌmp kɑːd]

美 [ˈtrʌmp kɑːrd]

n. 王牌; 绝招; 杀手锏

牛津词典

noun

王牌；绝招；杀手锏
something that gives you an advantage over other people, especially when they do not know what it is and you are able to use it to surprise them

noun

a playing card in the suit that has been declared trumps
1. the ace of trumps is a sure winner
Synonym:trump

The candidate still has one more trump card to play.
候选人手里还有一张王牌。
This is my trump card. I never use it easily.
这可是我的杀手锏，不轻易使用的！
But China also has a trump card that others don't:$ 3.2 trillion in cash reserves, by far the biggest hoard in the world.
但中国手里握有一张别国不具有的“王牌”：3.2万亿美元的外汇储备，这是全球规模最大的外储。
Now it's time that you played your trump card.
现在是你摊王牌的时候了。
His other trump card is his financial independence.
韩寒的另外一张王牌就是他的经济独立性。
She could threaten to play her trump card, an autobiography of embarrassing disclosures.
她可能会威胁要拿出她的杀手锏：出自传来爆料糗事。
Nor can we any longer fall back on our historical trump card of geographic isolation.
我们也不再能依靠天然屏障的历史王牌。
Not many people know it but shutting up can be the trump card in a lot of situations.
不是每个人都知晓这一点，但沉默在很多场合下的确是最好的王牌。
An unstoppable trump card with enough power to bring order to the world.
一张所向披靡的王牌将命令这个世界。
It is always good to enter negotiations with a trump card.
手握一张王牌去谈判总是件好事。