Error sounds good to me. I don't know if percent error and error mean the same thing to different people. Obviously they aren't quite the same.
The closeness of a measurement to its true value is a measure of its accuracy. Percent error is one way to quantitatively express the accuracy of a measurement. It is calculated by taking the absolute difference between the measured value and the true value, dividing it by the true value, and then multiplying by 100. Percent error allows us to determine how far off a measurement is from the actual or accepted value. A smaller percent error indicates a more accurate measurement.
