Synonyms for Vexation (same or very similar meaning)
WordNet sense 1 (the psychological state of being irritated or annoyed):
annoyance, irritation, botheration
WordNet sense 2 (anger produced by some annoying irritation):
chafe
WordNet sense 3 (something or someone that causes anxiety; a source of unhappiness):
concern, headache, worry
WordNet sense 4 (the act of troubling or annoying someone):
annoying
From the ODE community, based on WordNet
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