Tonkin

American  

[ton-kin, tong-] / ˈtɒnˈkɪn, ˈtɒŋ- /

Also Tongking

noun

1. a former state in northern French Indochina, now part of Vietnam.

2. Gulf of Tonkin, an arm of the South China Sea, west of Hainan. 300 miles (485 km) long.

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Tonkin British  

/ ˈtɒŋˈkɪŋ, ˈtɒnˈkɪn /

noun

1. a former state of N French Indochina (1883–1946), on the Gulf of Tonkin: forms the largest part of N Vietnam

2. an arm of the South China Sea, bordered by N Vietnam, the Leizhou Peninsula of SW China, and Hainan Island. Length: about 500 km (300 miles)

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Example Sentences

LBJ used the Tonkin Gulf resolution, which Congress overwhelmingly supported, to widen the war in Vietnam.

From The Wall Street Journal • Mar. 3, 2026

To do so, they used two isolated incidents of North Vietnamese patrol boats attacking a naval destroyer in the Gulf of Tonkin.

From Salon • Sep. 7, 2025

But the rich history, combined with the Cartier name and its rare and unique design, appeared to make the piece an irresistible prize for collectors, said Ms Tonkin.

From BBC • Jun. 6, 2025

The series compellingly addresses the Gulf of Tonkin incident, the baseless claims of William Westmoreland about impending victory, and the leaking of the Pentagon Papers.

From Slate • Apr. 30, 2025

While McNamara crossed the Potomac into Washington, the action in the Gulf of Tonkin continued.

From "Most Dangerous: Daniel Ellsberg and the Secret History of the Vietnam War" by Steve Sheinkin