wild card

US 
UK 
  • n.(由持牌人自由决定牌值的)百搭牌
  • Web外卡;万能牌;通配符
Plural Form:wild cards  
wild card
n.
1.
(由持牌人自由决定牌值的)百搭牌,变牌a card that has no value of its own and takes the value of any card that the player chooses
2.
“外卡”参赛,“外卡”选手(指没有正常参赛资格而参赛)an opportunity for sb to play in a competition when they have not qualified in the usual way; a player who enters a competition in this way
3.
通配符a symbol that has no meaning of its own and can represent any letter or number
4.
难以预测的人(或事物);未知因素;未知数a person or thing whose behaviour or effect is difficult to predict

Sample Sentence

Definition:
Category:AllAll,OralOral,WrittenWritten,TitleTitle,TechnicalTechnical
Source:AllAll,DictionaryDictionary,WebWeb
Difficulty:AllAll,EasyEasy,MiddleMiddle,HardHard