term used to designate obstructionist tactics in legislative assemblies. It has particular reference to the U.S. Senate, where the tradition of unlimited debate is very strong. It was not until 1917 that the Senate provided for cloture (i.e., the ending of the debate) by a vote of two thirds of the senators present; three fifths are now generally required. Yet, despite many attempts, cloture has been applied only rarely. The filibuster has been used by various blocs of senators for different purposes; for example, by conservatives resisting civil-rights legislation in the 1960s, and by liberals resisting cuts in the capital gains tax in 1991. At times the threat of a filibuster has been sufficient to prevent a bill from being debated and voted on. Bills favored by President Obama have been filibustered more often than those of any other president. The threat of a filibuster has also been used to prevent a vote on presidential nominees to executive and judicial posts, and in 2013 the Senate rules for those nominees were changed so that only a majority vote was required to end debate.
In the 17th cent. the word was applied to buccaneers who plundered the Spanish colonies in the New World. In the 19th cent. the term was used more in reference to adventurers who organized and led, under private initiative, armed expeditions into countries with which the country from which they set out was at peace. Complications between the governments involved were likely to result. There was a series of filibustering expeditions from the United States against Cuba, Mexico, and Central and South American countries in the 19th cent., some of them led by citizens of the United States, as those of John A. Quitman and William Walker, and some by rebellious citizens of the government they sought to overthrow, as those of Narciso López against Cuba. Texas, when it was still part of Mexico, was the scene of many such filibustering activities.
- For works on legislative filibusters, see Filibustering in the Senate (1940, repr. 1965),. ,
- Politics or Principle?: Filibustering in the United States Senate (1996),. ; ,
- Filibustering (2010), and. ,
- Defending the Filibuster (2012). ; ,
- For works on earlier senses of filibuster, see By-Ways of War: The Story of the Filibusters (1901),. ,
- The Sword Was Their Passport (1943), and. ,
- The Liberators (1973). ,
[16 century] Filibuster and freebooter  are doublets: that is to say, they come from the same ultimate source, but have subsequently...
To obstruct the passage of legislation through a parliament by making long speeches, raising constant procedural questions, etc. This tactic...
A method employed by some legislators to block business by uninterrupted speech-making. Most parliaments have adopted devices such as...