Đông Kinh, a former name of Hanoi, Vietnam

Gulf of Tonkin Incident, a 1964 naval incident that precipitated the Gulf of Tonkin Resolution

In France, the Sino-French War is termed the Tonkin War.

For the Battle of Tonkin and the Tonkin Affair of 1885, see Battle of Zhennan Pass.

Gulf of Tonkin Resolution, the 1964 resolution of the US Congress that precipitated the buildup of US forces in Vietnam

Tonkin Highway, a major arterial road in Perth, Western Australia

David Tonkin (1929–2000), Premier of South Australia 1979–1982

Tonkinese (cat), cat breed

Gulf of Tonkin, a gulf in the South China Sea

Tonkin, the northernmost part of Vietnam

Tonkin Street in Hong Kong

Anthony Tonkin (b. 1980), English professional football player

Phoebe Tonkin (contemporary), Australian actress

Humphrey Tonkin (b. 1939), American-British professor and Esperantist

John Tonkin (1902–1995), Premier of Western Australia 1971–1974

Felicity Tonkin (b. 1985), daughter of Mark Phillips and Heather Tonkin

William Tonkin (1897–[?]), British copperworker