S: https://archive.org/details/historyofbuccane00exqu (last access: 21 February 2014); http://www.pirates-privateers.com/definitions.htm (last access: 21 February 2014).
N: 1. 1560s, loan-translation of Dutch vrijbuiter “plunderer, robber,” from vrijbuiten “to rob, plunder,” from vrijbuit “plunder,” literally “free booty,” from vrij “free” + buit “booty,” from buiten “to exchange or plunder,” from Middle Dutch buten, related to Middle Low German bute “exchange” (see booty). See filibuster. The back-formed verb freeboot is recorded from 1590s.
2. filibuster (n.): 1580s, flibutor “pirate,” probably ultimately from Dutch vrijbuiter “freebooter,” a word which used of pirates in the West Indies in Spanish (filibustero) and French (flibustier) forms, either or both of which gave the word to American English (see freebooter).
Used 1850s and ’60s of lawless adventurers from the U.S. who tried to overthrow Central American governments. The legislative sense is not in Bartlett (1859) and seems not to have been in use in U.S. legislative writing before 1865. Probably the extension in sense is because obstructionist legislators “pirated” debate or overthrew the usual order of authority. Not technically restricted to U.S. Senate, but that’s where the strategy works best.
3. filibuster (v.): 1853 in both the freebooting and the legislative senses, from filibuster (n.). Related: Filibustered; filibustering.
4. Unlike a privateer, a freebooter went about plundering without the authority of national warfare.
5. Cultural Interrelation: The “freebooters” or “filibusters” traveled under no nation’s sail -they used various iterations of the Jolly Roger, instead – and often sought to “privateer” goods and gold being transported by Spanish ships in the Caribbean, from slaves to gold. The word to describe them was first recorded in English in the late 16th century, according to the Oxford English Dictionary.
S: 1, 2 & 3. OED – http://www.etymonline.com/index.php?allowed_in_frame=0&search=freebooter&searchmode=none (last access: 3 September 2014). 4. GDT. 5. http://www.theatlantic.com/politics/archive/2011/01/meet-the-first-filibusters-the-16th-and-17th-century-pirates-of-the-caribbean/68829/ (last access: 2 April 2015).
S: OD – http://www.oxforddictionaries.com/es/definicion/ingles/filibuster (last access: 3 September 2014)