bivouac
BIV-oo-ak
A temporary, minimal shelter or camp, often unplanned — a night spent on a ledge, in a snow cave, under a boulder, or simply wrapped in a bivy sack on open ground. The bivouac is where the mountain decides how you sleep.
Etymology
French: bivouac, from Swiss German Beiwacht (additional watch, night patrol). Originally a military term for temporary encampment.
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