The word for today is…
bivouac (noun) – A temporary encampment often in an unsheltered area.
(verb) – To camp in a bivouac.
Source : The Free Dictionary
Etymology : In the 1841 edition of An American Dictionary of the English Language, Noah Webster observed bivouac to be a French borrowing having military origins. He defined the noun bivouac as “the guard or watch of a whole army, as in cases of great danger of surprise or attack” and the verb as “to watch or be on guard, as a whole army.” The French word is derived from the Low German word biwacht, a combination of bi (“by”) and wacht (“guard”). In some German dialects, the word was used specifically for a patrol of citizens who assisted the town watch at night. Today, bivouac has less to do with guarding and patrolling and more about having shelter.