Quadrennial (?), a. [L. quadriennium a space of four years; quattuor four + annus year; cf. L. quadriennis. See Quadrate, and Annual.] 1. Comprising four years; as, a quadrennial period.[1913 Webster]
2. Occurring once in four years, or at the end of every four years; as, quadrennial games.[1913 Webster]