barrack (n.)
1680s, "temporary hut for soldiers during a siege," from French barraque, from Spanish barraca (mid-13c. in Medieval Latin) "soldier's tent," literally "cabin, hut," perhaps from barro "clay, mud," which is probably of Celt-Iberian origin. Meaning "permanent building for housing troops" (usually in plural) is attested from 1690s.