Synonyms for Rebuff (same or very similar meaning)
WordNet sense 1 (an instance of driving away or warding off):
repulse, snub
WordNet sense 2 (force or drive back):
repel, drive back, fight off
WordNet sense 3 (a deliberate discourteous act (usually as an expression of anger or disapproval)):
slight
From the ODE community, based on WordNet
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