E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
means huts made of the branches of trees (Gaelic, barr, the top of anything; barrach, the top-branches of trees; barrachad, a hut made of branches). Our word is plural, indicative of the whole collection; but the French baraque is singular. (See B. K. S.)