The Collaborative International Dictionary of English v.0.48:
Episodic \Ep`i*so"dic\, Episodical \Ep`i*so"dic*al\, a. [Cf. F. ['e]pisodique. See Episode.] Of or pertaining to an episode; adventitious. -- Ep`i*so"dic*al*ly, adv. [1913 Webster] Such a figure as Jacob Brattle, purely episodical though it be, is an excellent English portrait. --H. James. [1913 Webster]WordNet (r) 3.0 (2006):
episodically adv 1: in an episodic manner