International System of Units

noun
1.
an internationally accepted coherent system of physical units, derived from the MKSA (meter-kilogram-second-ampere) system, using the meter, kilogram, second, ampere, kelvin, mole, and candela as the basic units (SI units) respectively of the fundamental quantities of length, mass, time, electric current, temperature, amount of substance, and luminous intensity.
Abbreviation: SI.
Origin
translation of the earlier French name Système Internationale d'Unités
International System of Units in Medicine

International System of Units n.
Abbr. SI
A complete, coherent system of units used for scientific work, in which the fundamental quantities are length, time, electric current, temperature, mass, luminous intensity, and amount of substance. Also called International System.