Bastile Bastille \Bas*tile" Bas*tille"\, n. [F. bastille fortress, OF. bastir to build, F. b?tir.] 1. (Feud. Fort.) A tower or an elevated work, used for the defense, or in the siege, of a fortified place. The high bastiles . . . which overtopped the walls. --Holland. 2. ``The Bastille'', formerly a castle or fortress in Paris, used as a prison, especially for political offenders; hence, a rhetorical name for a prison.