RPM most commonly refers to revolutions per minute, although the abbreviation can also refer to other terms. RPM is a measure of frequency used in math, physics and engineering.
Revolutions per minute is the number of turns an object completes as it rotates along a fixed axis. RPM is not actually recognized as a unit in the International System of Units. Instead, the International System of Units uses hertz to measure frequency in cycles per second. However, many people still use the acronym RPM in everyday discussions of physical concepts, such as the speed produced by a motor or the speed at which a vinyl record is meant to be played.