contingency

n. possibility, chance

In philosophy and logic, contingency is the status of facts that are not logically necessarily true or false. Contingency is opposed to necessity: a contingent act is an act which could have not been, an act which is not necessary (could not have not been). Contingency differs from possibility, in a formal sense, as the latter includes statements which are necessarily true as well as not necessarily false, while a statement can not be said to be contingent if it is true necessarily.
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Noun
1. a possible event or occurrence or result
(synonym) eventuality, contingence
(hypernym) happening, occurrence, natural event
2. the state of being contingent on something
(hypernym) dependence, dependance, dependency

(n.)
Union or connection; the state of touching or contact.
  

(n.)
The quality or state of being contingent or casual; the possibility of coming to pass.
  

(n.)
An event which may or may not occur; that which is possible or probable; a fortuitous event; a chance.
  

(n.)
An adjunct or accessory.
  

(n.)
A certain possible event that may or may not happen, by which, when happening, some particular title may be affected.
  

an event that may or may not occur.