Contingent

1. n. That which falls to one in a division or apportionment among a number; a suitable share; proportion; esp., a quota of troops.
2. a. Possible, or liable, but not certain, to occur; incidental; casual.
3. a. Dependent on that which is undetermined or unknown; as, the success of his undertaking is contingent upon events which he can not control.
4. a. Dependent for effect on something that may or may not occur; as, a contingent estate.
5. n. An event which may or may not happen; that which is unforeseen, undetermined, or dependent on something future; a contingency.

The word meanings were obtained from OPTED(The Online Plain Text English Dictionary), which is based on “The Project Gutenberg Etext of Webster’s Unabridged Dictionary” which is in turn based on the 1913 US Webster’s Unabridged Dictionary (See Project Gutenburg), as a text file.