The process of comparing the reading or output of an instrument, device, or dial with a standard to determine the instrument's accuracy, capacity, or graduations is referred to as:

Calibration is the process of comparing the reading or output of an instrument with a known standard. This procedure establishes the accuracy of the instrument’s measurements and ensures that it operates within specified limits. By comparing it to a standard, adjustments can be made to align the instrument’s output with accepted values, thus ensuring precision in measurements.

Calibration is essential in various fields, including manufacturing and scientific research, to maintain quality control and data integrity. It helps to verify that the instrument is functioning correctly and provides an opportunity to identify any discrepancies that could lead to measurement errors. This not only enhances the reliability of the instrument but also reassures users that the data they are relying upon is accurate.

While other terms like differentiation, integration, and phase shifting are relevant in specific contexts, they do not pertain to the process of assessing and adjusting the accuracy of measurement instruments. Differentiation usually refers to a mathematical process, integration involves the summation of parts into a whole, and phase shifting is related to the alteration of the phase of a waveform, none of which relate to the comparison or adjustment of measurement outputs to standards.