Savai'i (sävī´ē), volcanic island (1981 pop. 43,150), Samoa. It is the largest (c.700 sq mi/1,810 sq km) and most westerly of the Samoan islands. Savai'i, fertile and mountainous, has the highest peak in Samoa, Mt. Silisili (6,070 ft/1,850 m). Bananas, copra, and cocoa are exported. The largest town is Tuasivi. Savai'i was formerly called Chatham Island.