n. & v.
n. (pl. -oes) 1 a a constitutional right to reject a legislative enactment. b the right of a permanent member of the UN Security Council to reject a resolution. c such a rejection. d an official message conveying this. 2 a prohibition (put one's veto on a proposal).
v.tr. (-oes, -oed) 1 exercise a veto against (a measure etc.). 2 forbid authoritatively. vetoer n.
[ L, = I forbid, with ref. to its use by Roman tribunes of the people in opposing measures of the Senate ]