sign off on vs veto

sign off on

veto

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. 

verb
  • To use a veto against. 

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