Synonyms: sporadic
Definition: recurring in scattered and irregular or unpredictable instances
Usage: a city subjected to sporadic bombing raids
Similar words: spasmodic, fitful
Definition: occurring in spells and often abruptly
Usage: fitful bursts of energy; spasmodic rifle fire
Similar words: intermittent
Definition: stopping and starting at irregular intervals
Usage: intermittent rain showers
Similar words: periodic, occasional
Definition: recurring or reappearing from time to time
Usage: periodic feelings of anxiety
Similar words: unpredictable, irregular
Definition: not occurring at expected times
Similar words: isolated, stray
Definition: not close together in time
Usage: isolated instances of rebellion; a few stray crumbs