Episodical, Episodic adj. Of or pertaining to an episode; adventitious. "Such a figure as Jacob Brattle, purely episodical though it be, is an excellent English portrait."
... general statistical grounds at first in the Not Unpleasant group, Case VI should be transferred to the Unpleasant group. Case V's delusion (identification with God, expression of atonement?) was in any event episodic in a septicemia. Case IV ("happiest woman in the world"), was phthisical ... — The Journal of Abnormal Psychology - Volume 10