Synonyms for Dissentient (same or very similar meaning)
WordNet sense 1 ((of Catholics) refusing to attend services of the Church of England):
recusant
WordNet sense 2 (breaking with convention or tradition):
unorthodox
WordNet sense 3 (disagreeing, especially with a majority):
dissident, dissenting
WordNet sense 4 (expressing or consisting of a negation or refusal or denial):
negative
From the ODE community, based on WordNet
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