Synonyms for Irregularity (same or very similar meaning)
WordNet sense 1 (irregular and infrequent or difficult evacuation of the bowels; can be a symptom of intestinal obstruction or diverticulitis):
constipation
WordNet sense 2 (an irregular asymmetry in shape; an irregular spatial pattern):
geometrical irregularity
WordNet sense 3 (not characterized by a fixed principle or rate; at irregular intervals):
unregularity
WordNet sense 4 (behavior that breaches the rule or etiquette or custom or morality):
abnormality
From the ODE community, based on WordNet
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