Hán Việt

Sino-Vietnamese vocabulary (Vietnamese: Từ Hán Việt, Chữ Nôm: 詞漢越, literally "Sino-Vietnamese words") are words and morphemes of the Vietnamese language borrowed from Chinese. They comprise about a third of the Vietnamese lexicon, and may account for as much as 60% of the vocabulary used in formal texts. This vocabulary was originally written with Chinese characters that were used in the Vietnamese writing system, but like all written Vietnamese, is now written with the Latin-based Vietnamese alphabet that was adopted in the early 20th century.

Together with Sino-Korean and Sino-Japanese vocabularies, Sino-Vietnamese has been used in the reconstruction of the sound categories of Middle Chinese. Samuel Martin (1953) grouped the three together as "Sino-xenic".

As a result of a thousand years of Chinese control (except for brief rebellions), and a further thousand years of strong Chinese influence, two main layers of Chinese vocabulary have been borrowed into Vietnamese. These layers were first systematically studied by Wang Li.Middle Chinese and Vietnamese (like other nearby languages) are of analytic type, with almost all morphemes monosyllabic and lacking inflection. The phonological structure of their syllables is also similar.

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