The etymology of Zhou(周):

There are evidences that boat(舟, bae by Korean) has been used since prehistoric era . According to the Shiji, they made a floating bridge with boats (造舟為梁). They used animal skin to make a boat . They also used Bak(瓠; hù hú huò gū, Bak/박 by Korean. Boat and Bak derived from opposite phenomena of darkness. Wu the great used boat(舟) and a sledge (橇) to travel around swamp to control the epic flood . Northern barbarian came down to the Nine Provinces developed all the basic tools,tamed wild animals, and many logograms as pointed out before.
Alien came from the east of Han-gu pass adapted the local culture, used the boat(舟) to travel around the original Nine Provinces, and named the new kingdom as Zhou (周) meaning every corner by the boat. For the practical reason, they set the capital at the middle of the territory (于中國), which is the origin of Middle Kingdom and defining point of directions.