Synonyms for Fitful (same or very similar meaning)
WordNet sense 1 (occurring in spells and often abruptly):
spasmodic
WordNet sense 2 (recurring in scattered and irregular or unpredictable instances):
sporadic
WordNet sense 3 (intermittently stopping and starting):
interrupted, off-and-on
WordNet sense 4 (not continuous in space, time, or sequence or varying abruptly):
broken
From the ODE community, based on WordNet
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