veto

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. The vested power or constitutional right of one branch or department of government to refuse approval of measures proposed by another department, especially the power of a chief executive to reject a bill passed by the legislature and thus prevent or delay its enactment into law.
2. n. Exercise of this right.
3. n. An official document or message from a chief executive stating the reasons for rejection of a bill.
4. n. An authoritative prohibition or rejection of a proposed or intended act.
5. v. To prevent (a legislative bill) from becoming law by exercising the power of veto.
6. v. To forbid or prohibit authoritatively.

Century Dictionary and Cyclopedia

1. n. In a constitutional government, the right vested in one branch of it to negative the determinations of another branch; specifically, the right, under constitutional restrictions, of the executive, as a king, a president, or a governor, to reject a bill passed, by the legislature; also, the act of exercising this right. This power is often traced to the privilege enjoyed by the Roman tribunes of annulling or suspending any measures of the senate, decree of a magistrate, etc., the word veto (I forbid) having been at least occasionally used by the tribune in such a case. This power of the tribunes was properly called intercessio. The attempt on the part of Louis XVI. of France to exercise the veto assured to him by the Constitution of 1791 was one of the causes of the revolutionary movements of 1792, which at once dethroned the king and overturned the Constitution. In Great Britain the power of the crown is confined to a veto, a right of rejecting and not resolving, and even this right has become practically obsolete, the last occasion of its exercise being in the reign of William III. The Constitution of the United States provides that “every Bill which shall have passed the House of Representatives and the Senate, shall, before it become a Law, be presented to the President of the United States. If he approve, he shall sign it; but if not, he shall return it with his Objections to that House in which it shall have originated, who shall enter the Objections at large on their Journal, and proceed to reconsider it. If after such Reconsideration two-thirds of that House shall agree to pass the Bill, it shall be sent, together with the Objections, to the other House, by which it shall likewise be reconsidered, and if approved by two-thirds of that House, it shall become a Law. … If any Bill shall not be returned by the President within ten Days (Sundays excepted) after it shall have been presented to him, the Same shall be a Law, in like Manner as if he had signed it, unless the Congress by their Adjournmeut prevent its Return, in which Case it shall not be a Law.” (Article I. Sec. 7.) Most of the State Constitutions have a similar provision.
2. n. Any right or power of authoritatively forbidding or effectively negativing, or the exercise of such right or power; prohibition; interdict.
3. To forbid authoritatively; specifically, to negative by exercising the constitutional right of veto: as, to veto a bill.

Wiktionary

1. n. A political right to disapprove of (and thereby stop) the process of a decision, a law etc.
2. n. An invocation of that right.
3. v. To use a veto against.

GNU Webster's 1913

1. n. An authoritative prohibition or negative; a forbidding; an interdiction.
2. n. 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.
3. n. The exercise of such authority; an act of prohibition or prevention.
4. n. A document or message communicating the reasons of the executive for not officially approving a proposed law; -- called also veto message.
5. v. To prohibit; to negative; also, to refuse assent to, as a legislative bill, and thus prevent its enactment.

WordNet 3.0

1. n. 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)
2. n. a vote that blocks a decision
3. v. vote against; refuse to endorse; refuse to assent
4. v. command against