a vote that blocks a decision
"The mayor used his veto to block the council's decision to raise property taxes."
the power or right to prohibit or reject a proposed or intended act (especially the power of a chief executive to reject a bill passed by the legislature)
"The president used his veto power to block the controversial infrastructure bill before it could become law."
A political right to disapprove of (and thereby stop) the process of a decision, a law etc.
"The President used his veto power to block the controversial bill from becoming law."
To use a veto against.
"The city council voted to approve the new park, but the mayor used his veto against it."