blackball vs veto

blackball

verb
  • To vote against, especially in an exclusive organization. 

  • To ostracize. 

noun
  • A black ball used to indicate such a negative vote. 

  • A rejection; a vote against admitting someone. 

  • A kind of large black sweet; a niggerball. 

  • A game, a standardized version of the English version of eight-ball. 

  • A substance for blacking shoes, boots, etc. or for taking impressions of engraved work. 

veto

verb
  • To use a veto against. 

noun
  • An invocation of that right. 

  • A technique or mechanism for discarding what would otherwise constitute a false positive in a scientific experiment 

  • A political right to disapprove of (and thereby stop) the process of a decision, a law etc. 

  • An authoritative prohibition or negative; a forbidding; an interdiction. 

How often have the words blackball and veto occurred in a corpus of books? (source: Google Ngram Viewer )