SI unit /es ˈaɪ ˌjuːnət/ BrE AmE noun [countable] technical
a standard unit of measurement in an international system used especially by scientists. SI units include the metre, kilogram, second, AMPERE , and ↑ Kelvin .
SI unit /es ˈaɪ ˌjuːnət/ BrE AmE noun [countable] technical
a standard unit of measurement in an international system used especially by scientists. SI units include the metre, kilogram, second, AMPERE , and ↑ Kelvin .
Longman Dictionary of Contemporary English. Longman - Словарь современного английского языка. 2012