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Synonyms for Aggravation (same or very similar meaning)

WordNet sense 1 (an exasperated feeling of annoyance):

WordNet sense 2 (unfriendly behavior that causes anger or resentment):
irritation, provocation

WordNet sense 3 (action that makes a problem or a disease (or its symptoms) worse):

From the ODE community, based on WordNetadd/edit