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English definition of “SI”

SI

noun     /ˌesˈaɪ/ MEASURES
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): The chart shows you how to convert from a conventional unit to an SI unit.
UK LAW →  statutory instrument
(Definition of SI noun from the Cambridge Business English Dictionary © Cambridge University Press)
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