\Ve"to\, n.; pl. {Vetoes}. [L. veto I forbid.]
1. An authoritative prohibition or negative; a forbidding; an
   interdiction.
         This contemptuous veto of her husband's on any
         intimacy with her family.             --G. Eliot.
2. Specifically:
   (a) A power or right possessed by one department of
       government to forbid or prohibit the carrying out of
       projects attempted by another department; especially,
       in a constitutional government, a power vested in the
       chief executive to prevent the enactment of measures
       passed by the legislature. Such a power may be
       absolute, as in the case of the Tribunes of the People
       in ancient Rome, or limited, as in the case of the
       President of the United States. Called also {the veto
       power}.
   (b) The exercise of such authority; an act of prohibition
       or prevention; as, a veto is probable if the bill
       passes.
   (c) A document or message communicating the reasons of the
       executive for not officially approving a proposed law;
       -- called also {veto message}. [U. S.]
Note: Veto is not a term employed in the Federal
      Constitution, but seems to be of popular use only.
      --Abbott.

\Ve"to\, v. t. [imp. & p. p. {Vetoed}; p. pr. & vb. n.
{Vetoing}.]
To prohibit; to negative; also, to refuse assent to, as a
legislative bill, and thus prevent its enactment; as, to veto
an appropriation bill.