Contingent (?), a. [L. contingens, -entis, p. pr. of contingere to touch on all sides, to happen; con- + tangere to touch: cf. F. contingent. See Tangent, Tact.] 1. Possible, or liable, but not certain, to occur; incidental; casual.
[1913 Webster]

Weighing so much actual crime against so much contingent advantage. Burke.
[1913 Webster]

2. Dependent on that which is undetermined or unknown; as, the success of his undertaking is contingent upon events which he can not control. “Uncertain and contingent causes.” Tillotson.
[1913 Webster]

3. (Law) Dependent for effect on something that may or may not occur; as, a contingent estate.
[1913 Webster]

If a contingent legacy be left to any one when he attains, or if he attains, the age of twenty-one. Blackstone.
[1913 Webster]