Tonga Trench

American  

[tong-guh trench] / ˈtɒŋ gə ˈtrɛntʃ /

noun

1. an oceanic trench in the South Pacific Ocean that lies as a nearly linear stretch from the northern end of the Kermadec Trench northward to an area south of Samoa, with rates of convergence along the two trenches’ subduction system being among the world’s fastest: the deepest trench in the Southern Hemisphere and the site of the Horizon Deep.

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Etymology

Origin of Tonga Trench

First recorded in 1910–15; named after the Tonga archipelago

Example Sentences

See Examples For:

Tonga Trench

Judah explained that the Tonga Trench sighting also establishes a new depth record for the entire order of Lamniformes, also known as the mackerel sharks.

From Science Daily ● Jul. 8, 2026

The second encounter occurred during a 2024 expedition to the Tonga Trench aboard the R/V Dagon as part of the Inkfish Open Ocean Expedition, led by scientists from the Minderoo-UWA Deep-Sea Research Center.

From Science Daily ● Jul. 8, 2026

"I was also very surprised about how deep this species was found. The observation from the slope of the Tonga Trench is nearly 700 meters deeper than this species was known to live."

From Science Daily ● Jul. 8, 2026

And Prof Jamieson will shortly be undertaking dives in Bakunawa that will investigate the world's second deepest location - Horizon Deep, in the Pacific's Tonga Trench, where the seafloor is 10,816m below the surface.

From BBC ● May 16, 2024

Vescovo tells the writer when they meet aboard his ship en route to the Tonga Trench.

From Scientific American ● Jun. 20, 2023