Calibration comes from measurement technology. It is the process of comparing a measurement made by a device with a standard, e.g., voltage, meters, or fraud/not fraud.
A difference between the standard and the measurement indicates that the device has a calibration error. It does not measure the standard correctly. It is biased. In practice, all devices are biased, and the challenge is to minimize that bias.
- By NOAA's National Ocean Service (Tracking the Ball) [Public domain]