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Synonyms for Vindictive (same or very similar meaning)

WordNet sense 1 (disposed to seek revenge or intended for revenge):
revengeful, vengeful

WordNet sense 2 (unwilling or unable to forgive or show mercy):

WordNet sense 3 (showing malicious ill will and a desire to hurt; motivated by spite):
spiteful, despiteful

WordNet sense 4 (having the nature of or resulting from malice):

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