An Etymological Dictionary of the German Language/Annotated/Boot
Boot, neuter ‘boat,’ Modern High German only (not found in Luther), borrowed from Low German boot; compare the equivalent Dutch boot, Anglo-Saxon bât, English boat, Old Icelandic beitr. This word, which is still unknown to the Upper German dialects, is at all events native to England, whence it made its way during the Anglo-Saxon period into Old Icelandic (bátr), and in Middle English times to the Continent (Dutch boot). The origin of Anglo-Saxon bât, Old Icelandic beitr, has not been discovered; like many other nautical terms, this word too is first recorded in English. Moreover, the assumption that the word was borrowed in primitively Teutonic times must be discarded.