Shaku (unit)

Short description: Traditional Japanese unit of length

Unit system	Japanese units
Unit of	length
Symbol	尺
Conversions
1 尺 in ...	... is equal to ...
SI units	0.3030 m
Imperial/US units	0.9942 ft 11.93 in

Shaku (Japanese: 尺) or Japanese foot is a Japanese unit of length derived (but varying) from the Chinese , originally based upon the distance measured by a human hand from the tip of the thumb to the tip of the forefinger (compare span). Traditionally, the length varied by location or use, but it is now standardized as 10/33 m, or approximately 30.3 centimeters (11.9 in).

Etymology in English

entered English in the early 18th century, a romanization of the Japanese Go-on reading of the character for Japanese foot (尺, shaku).

Use in Japan

The had been standardized as 30.3 cm (11.93 in) since 1891. This means that there are about 3.3 (​¹⁰⁄₃₃) to one meter.

The use of the unit for official purposes in Japan was banned on March 31, 1966, although it is still used in traditional Japanese carpentry and some other fields, such as kimono construction. The traditional Japanese bamboo flute known as the ( and ) derives its name from its length of one and eight . Similarly, the remains in use in the Japanese lumber trade. In the Japanese construction industry, the standard sizes of drywall, plywood, and other sheet goods are based on , with the most common width being three (rounded up to 910 mm (35.83 in)).

In Japanese media parlance, refers to screen time: the amount of time someone or something is shown on screen (similar to the English "footage").

History

Traditionally, the actual length of the varied over time, location, and use. By the early 19th century, the was largely within the range of 0.30175 to 0.303 meters (11.880 in to 11.929 in), but a longer value of the (also known as the ) was also known, and was 1.17 times longer than the present value (35.5 centimeters or 14.0 inches).

Carpenter's unit and tailor's unit

Another variant was used for measuring cloth, which measured ​¹²⁵⁄₃₃₀ meters (37.9 centimeters or 14.9 inches), and was known as the "whale " (鯨尺, kujirajaku), as baleen (whale whiskers) were used as cloth rulers.

To distinguish the two variants of , the general unit was known as the "metal " (金尺/曲尺, kanejaku). The Shōsōin treasure house in Nara preserves some antique ivory one- rulers, known as the kōgebachiru-no-shaku (紅牙撥鏤尺).

Derived units

Length

Just as with the Chinese unit, the is divided into ten smaller units, known as sun (寸) in Japanese, and ten together form a larger unit known in Japanese as a jō (丈). The Japanese also had a third derived unit, the , equal to six ; this was used extensively in traditional Japanese architecture as the distance between supporting pillars in Buddhist temples and Shinto shrines.

Volume

Ten cubic comprised a , reckoned as the amount of rice necessary to sustain a peasant for a year.

Outside Japan

The Japanese also forms the basis of the modern Taiwanese foot.

In 1902, the Korean Empire adopted the Japanese definition of the as that of the (자).

See also

• Japanese units of measurement

Bibliography

• Weiner, E. S. C. (2004). The Oxford English Dictionary. Oxford University Press. ISBN 0-19-861227-3.