Sumatra

 Longman Dictionary of Contemporary English Online朗文当代英语 5++LDOCE Online朗文 5++Su·ma·tra /sʊˈmɑːtrə/  the second largest of the islands that form the country of Indonesia. Its largest city is Padang. —Sumatran noun, adjective

Su·ma·traSyllable  

Sumatra
Su‧ma‧tra /sʊˈmɑːtrə/
the second largest of the islands that form the country of Indonesia. Its largest city is Padang.
—Sumatran noun, adjective