Old English earc, Old Northumbrian arc, mainly meaning Noah's but also the Ark of the Covenant, from Latin arca "large box, chest" (see arcane), the word used in the Vulgate. Also borrowed in Old High German (arahha, Modern German Arche). From the Noachian sense comes extended meaning "place of refuge" (17c.). As the name of a type of ship or boat, from late 15c. In 19c. U.S., especially a large, flat-bottomed river boat to move produce, livestock, etc. to market.