Bohai Sea /ˈboʊhaɪsiː/ noun1 •A gulf of the Yellow Sea in the northern Pacific Ocean beside Shandong, Hebei, Tianjin, and Liaoning on the northeastern coast of mainland China.Another crisis, the deaths of 70 officers and sailors aboard submarine No. 361 in the Bo Hai Sea in late April, further illustrated Hu's new way of doing business, analysts said. — 2003