stopwatch

This device is characterized by its ability to be started and stopped manually, distinguishing it from a standard clock or watch that tracks the continuous flow of the day. It is primarily associated with precision, competition, and the measurement of duration rather than the identification of the current time. In modern usage, the physical handheld device has largely been superseded by digital applications on smartphones and smartwatches, though the term remains the standard designation for the function of measuring elapsed time.