A bastion is a stronghold, preserving something in short supply. But a bastion is a stronghold in a more literal sense, too. It’s a fortress. Knowing that, you might have figured out that bastion comes from bastille. Since the French Revolution, Bastille has meant one specific fortress. Why this name? Before French, the Provençal bastir meant “to build,” as in making something from bast, or bast tissue. You’ll find bast in baste, the verb that means, among other things, stitching something loosely.
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