Synonyms for Blackball (same or very similar meaning)
WordNet sense 1 (expel from a community or group):
ban, banish, ostracize, shun, ostracise, cast out
WordNet sense 2 (vote against; refuse to endorse; refuse to assent):
negative, veto
WordNet sense 3 (the act of excluding someone by a negative vote or veto):
barring
From the ODE community, based on WordNet
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