contingency

noun4

1. •
   The quality of being contingent, of happening by chance.
2. •
   A possibility; something which may or may not happen. A chance occurrence, especially in finance, unexpected expenses.

   • There was also the imperative necessity of creating a reserve fund for unforeseen contingencies, and the question ever present was how was money to be found. — 1909
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 they do not fulfill the contract according to the specification.
4. •
   A statement which is neither a tautology nor a contradiction.