a. Of or pertaining to the doctrine of philosophical necessity in regard to the origin and existence of things, especially as applied to the actings or choices of the will; -- opposed to
n. One who holds to the doctrine of necessitarianism. [ 1913 Webster ]
n. The doctrine of philosophical necessity; the doctrine that results follow by invariable sequence from causes, and esp. that the will is not free, but that human actions and choices result inevitably from motives; determinism. M. Arnold. [ 1913 Webster ]