What is the commonly used system of measurement in the United States referred to as?

The commonly used system of measurement in the United States is referred to as the Customary system. This system is based on units such as feet, pounds, and gallons, which are typically used for everyday activities like measuring distance, weight, and volume. The Customary system has historical roots in the British Imperial system, but it has evolved uniquely within the context of American measurements.

The other options refer to different systems of measurement. The Imperial system, while related and historically similar, is officially used in the United Kingdom and includes different standards. The SI system, or International System of Units, is a modern metric system used globally and is not typically used for everyday measurements in the U.S. The Metric system is another form of measurement that uses units like meters and kilograms, but it is not the primary system used in everyday American life. Hence, the Customary system is the most accurate term for the context of measurements predominantly used in the United States.