From Italian 'bastione' (large fortification), from 'bastire' (to build) — entered English during the great age of European fortress design.
A projecting part of a fortification; a stronghold or institution defending a principle.
From French 'bastion,' from Italian 'bastione' (large fortification, augmentative of 'bastia' meaning fortress), from 'bastire' (to build). Ultimately traces to a Germanic root *bastjan (to build with bast/wicker), related to Old High German 'besten' (to mend, to patch with bast fiber). The term entered English during the 16th century when European military architecture was
The word entered English during the age when European military architecture was being transformed by the need to resist cannon fire, and star-shaped bastions replaced medieval towers.