noun
relative error
Technical term used in mathematics, statistics, and engineering to express the error of a measurement relative to the true value.
測定値の相対誤差を計算する。
Calculate the relative error of the measured value.
絶対誤差 is absolute error, the raw difference between measured and true values, while 相対誤差 expresses that difference as a fraction or percentage of the true value.
Compound of 相対 (relative) and 誤差 (error). The exact historical derivation is uncertain, but the term is a straightforward technical calque from English 'relative error'.