DionysiacPronunciation: /ˌdʌɪəˈnɪzɪak/ (also Dionysian /-zɪən/)Definition of Dionysiac adjective 1 Greek Mythology relating to the god Dionysus. 2relating to the sensual, spontaneous, and emotional aspects of human nature. Compare with Apollonian.Dionysiac in other Oxford dictionaries Definition of Dionysiac in the US English dictionary