Metric BASE is a system of measurement that uses the metric system as its BASE. It is a decimal system of measurement, meaning that all measurements are based on multiples of 10. This system is used in many countries around the world and is the most widely used system of measurement. The term METRIC BASE is composed of three words: METRIC, which refers to the metric system; BASE, which refers to the BASE unit of measurement; and TEN, which refers to the fact that the system is based on multiples of 10.