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

See Examples For:

Sumatra

Anak Krakatau, which means Child of Krakatau, sits in a strait that separates the islands of Java and Sumatra.

From Barron's ● Sep. 7, 2026

Thick smog has blanketed parts of Indonesia as the vast archipelago for weeks battles to contain fires that have burned large swathes of Borneo and Sumatra.

From Barron's ● Sep. 5, 2026

Thismia daemona belongs to Thismia section Geomitra, which had previously been documented only in Peninsular Malaysia, Borneo and Sumatra.

From Science Daily ● Sep. 4, 2026

Many of the ongoing fires have been burning across Sumatra and Indonesian Borneo since mid-July – underpinned by a so-called Super El Niño that is exacerbating drought conditions.

From BBC ● Sep. 3, 2026

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