Filibuster \Fil"i*bus*ter\, v. i. [imp. & p. p. {Fillibustered}; p. pr. & vb. n. {Filibustering}.] 1. To act as a filibuster, or military freebooter. --Bartlett. 2. To delay legislation, by dilatory motions or other artifices. [political cant or slang, U.S.] --Bartlett.