contingency

noun

1. 1

   The quality of being contingent, of happening by chance; unpredictability.

2. 2

   A possibility; something which may or may not happen. A chance occurrence, especially in finance, unexpected expenses.

3. 3

   An amount of money which a party to a contract has to pay to the other party (usually the supplier of a major project to the client) if he or she does not fulfill the contract according to the specification.

4. 4

   A statement which is neither a tautology nor a contradiction.