Collins COBUILD Advanced Learner's English Dictionary - wild card

also wildcard (wild cards) 1. If you refer to someone or something as a wild card in a particular situation, you mean that they cause uncertainty because you do not know how they will behave. The wild card in the picture is eastern Europe. N-COUNT: oft N in n 2. If a sports player is given a wild card for a particular competition, they are allowed to play in it, although they have not qualified for it in the usual way. You can also use wild card to refer to a player who enters a competition in this way. N-COUNT 3. A wildcard is a symbol such as * or ? which is used in some computing commands or searches in order to represent any character or range of characters. (COMPUTING) N-COUNT