Vietnamese numerals

Historically Vietnamese has two sets of numbers: one is etymologically native Vietnamese; the other uses Sino-Vietnamese vocabulary. In the modern language the native Vietnamese vocabulary is used for both everyday counting and mathematical purposes. The Sino-Vietnamese vocabulary is used only in fixed expressions or in Sino-Vietnamese words. This is somewhat analogous to the way in which Latin and Greek numerals are used in modern English (e.g., the bi- in bicycle). Sino-Vietnamese words are also used for units of ten thousand or above, where native vocabulary was lacking.

Among the languages of the Chinese cultural sphere, Japanese and Korean both use two numerical systems, one native and one Chinese-based. The Chinese-based vocabulary is the one in common use. In Vietnamese, on the other hand, the Chinese-based system is not in everyday use. Numbers from 1 to 1000 are expressed using native Vietnamese vocabulary, and only a few numbers (such as 1,000,000, triệu) are based on Sino-Vietnamese vocabulary.

In the modern Vietnamese writing system, numbers are written in the romanized script quốc ngữ or Arabic numerals. Prior to the 20th century Vietnam officially used Classical Chinese as a written language, using Chinese characters to write Sino-Vietnamese numbers. For non-official purposes Vietnamese also had a writing system known as Hán-Nôm. Under this system, Sino-Vietnamese numbers were written in Hán tự (Chinese characters) and native vocabulary was written in a system of modified Chinese characters known as Chữ Nôm.

Basic features of the Vietnamese numbering system include the following:

The following table is an overview of the basic Vietnamese numeric figures, provided in both Native and Sino-Viet forms. For each number, the form that is more commonly used is highlighted. Where there are differences between the Hanoi and Saigon dialects of Vietnamese, readings between each are differentiated below within the notes.

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