[f. FILIBUSTER sb. + -ISM.] The practice of filibustering; inclination to, or tendency to support, filibustering.
1862. J. Spence, The American Union, 74. Filibusterism is another branch of the same tree [as Repudiation].
1886. The American, XII. 25 Sept., 361/2. Fremont and Stockton had a plausible claim to be considered conquerors, but Mr. Bancrofts detail of the facts fully proves that their blunders, braggadocio and filibusterism had excited the troubles which called forth their energetic military efforts.