Sumatra

American  

[soo-mah-truh] / sʊˈmɑ trə /

noun

1. a large island in the W part of Indonesia. 164,147 sq. mi. (425,141 sq. km).

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Sumatra British  

/ sʊˈmɑːtrə /

noun

1. Indonesian spellling: Sumatera.  a mountainous island in W Indonesia, in the Greater Sunda Islands, separated from the Malay Peninsula by the Strait of Malacca: Dutch control began in the 16th century; joined Indonesia in 1945. Northern coastal areas, esp Aceh province, suffered devastation as a result of the Indian Ocean tsunami of December 2004. Pop: 42 409 510 (2000). Area: 473 606 sq km (182 821 sq miles)

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Sumatra Cultural  

1. Island in Indonesia in the Indian Ocean northwest of Java and west of Malaysia.

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Discover More

Though much of the island is covered by swampland and impenetrable rain forest, Sumatra's industries — including oil, coal, gold, silver, rubber, timber, and tobacco — produce over half of Indonesia's income.

Other Word Forms

• Sumatran adjective

Example Sentences

The only documented example occurred in Sumatra, where two large earthquakes struck three months apart in 2004 and 2005.

From Science Daily • May 2, 2026

Officials from President Prabowo Subianto down have acknowledged the role of deforestation and overdevelopment in last year's flooding and landslides, which killed over 1,000 people in Sumatra.

From Barron's • Feb. 19, 2026

But ever since Cyclone Senyar devastated Sumatra on 25 November, the critically endangered primates have not been seen in the area, conservation workers say.

From BBC • Dec. 11, 2025

Pictures showing the carcass of a Sumatran elephant, another critically endangered species, being swept away by floods in Aceh in northern Sumatra went viral on social media last week.

From BBC • Dec. 11, 2025

The last supervolcano eruption on Earth was at Toba, in northern Sumatra, seventy-four thousand years ago.

From "A Short History of Nearly Everything" by Bill Bryson