BIVOUAC, b?v'w?k (Fr., probably from Ger. Beiwache, Beiwacht, from bei, by + Wache, watch, guard), Military. An encampment of soldiers in the open air; generally of a temporary nature. In active service, and in an enemy's country, great care must be exercised in the choice of ground for a bivouac. It must be, as far as possible, free from being commanded by artillery fire, capable of hasty defense, offer few (if any) advantages to an enemy, and be rear water facilities for men and animals. See Encampment; Camp, Military; and Cantonment.