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

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。
'What's her trump card?
什么是她的王牌呀？
Proximity to America, Mexico's trump card, has been made more valuable by the high oil price.
邻近美国是墨西哥的王牌，这使得高油价更有价值。
In the end, the Ten took their appeal to the Supreme Court; this, they had believed from the outset, would be their trump card
最后，10个人上诉到最高法院：他们从一开始就认为这一招是他们的王牌。
Jack showed his trump card at the last minute.
杰克在最后一刻打出了王牌。
When his father refused to let him have his own way, the child played his trump card by crying.
看到爸爸没有如自己的意，那孩子便使出绝招，哇的一声哭了起来。
The opponent has to play his trump card to secure his third trick.
对方只好打出将牌以赢得第三墩牌。
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。
But the real disappointment for Yahoo shareholders is that the company threw away its trump card so cheaply.
但真正令雅虎股东失望的是，雅虎如此轻易地丢掉了自己的王牌。
The candidate still has one more trump card to play.
候选人手里还有一张王牌。