0 abbreviation for Système International: the international system of units used for scientific measurements, with standard base units such as the metre and the kilogram: --
1 abbreviation for International System of Units (= an international system of units used for measurement in scientific work) --
2 abbreviation for Système International: a system of units of measurement used internationally. SI units include the metre, kilogram, second, ampere (= unit of electric current), candela (= unit of light), kelvin (= unit of temperature), and the mole (= unit of the amount of a substance): --
3 → statutory instrument --