Synonyms for Suppression (same or very similar meaning)
WordNet sense 1 (the act of withholding or withdrawing some book or writing from publication or circulation):
curtailment
WordNet sense 2 (forceful prevention; putting down by power or authority):
crushing, stifling, quelling
WordNet sense 3 ((psychology) the conscious exclusion of unacceptable thoughts or desires):
inhibition
From the ODE community, based on WordNet
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