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Synonyms for Caustic (same or very similar meaning)

WordNet sense 1 (harsh or corrosive in tone):
acerbic, acid, acrid, bitter, blistering, sulfurous, venomous, virulent, vitriolic, acerb, sulphurous

WordNet sense 2 (disagreeable to the senses, to the mind, or feelings ):

WordNet sense 3 (of a substance, especially a strong acid; capable of destroying or eating away by chemical action):
corrosive, erosive, mordant

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