metric system

The system of units developed in France in the 1790s and now used worldwide.

The modern version of that system, Système International d'Unités (International System of Units), or SI that is based on the base units of the meter/metre, the kilogram, the second, the ampere, the kelvin, the mole, and the candela.

Any variant of that system, that was not codified as SI, such as cgs.