or Talcaguano, a seaport of the province of Concepcion, Chile, on the bay of Concepcion, 8 m. N.W. of the city and port of that name. Pop. (1895) 10,431; (1902, estimated) 13,499. It is sheltered by the island of Quiriquina. It has the best harbour on the Pacific coast of South America, and is one of the most important ports of southern Chile, being connected by rail with Concepcion, Santiago and southern Chile. Its foreign trade is large and steadily increasing. The Chilean government has established its chief naval depot here.