Si (simplified Chinese: 丝; traditional Chinese: 絲; pinyin: sī) is a traditional Chinese unit of length. One si is equal to 1/10 of a hao, 1/100 000 of a chi, or 3+1⁄3 μm. In the field of engineering, one si equals 10 μm.
Contents
Present law on Chinese length units
This law of length measurement was issued by the Chinese government in 1929, and has been effective since 1 January 1930. The base unit chi is defined to be 1/3 meter.
Metric length units
These units are based on the metric system. The Chinese word for metre is 米 mǐ, which can take the Chinese standard SI prefixes (for "kilo-", "centi-", etc.). In the engineering field, traditional units are rounded up to metric units.
Compounds
絲毫 (sīháo)
一絲一毫 (yīsīyīháo)
一絲不苟
一絲 希望／一丝 希望 ― yī sī xīwàng ― a glimmer of hope.
