MIL STD- Definitions of Terms for Testing, Measurement and Diagnostics

3. DEFINITIONS
3.1 Definitions of terms used in this standard. The following definitions shall apply to the terms stated.

3.1.1 Absolute error.
The magnitude of the error without regard to algebraic sign.

3.1.2 Absolute measurement.
The measurement in which the comparison is directly with quantities whose units are basic units of the system. Notes: (a) For example, the measurement of speed by measurements of distance and time is an absolute measurement, but the measurement of speed by a speedometer is not an absolute measurement. (b) The word absolute implies nothing about precision or accuracy.

3.1.3 Accelerated life test.
A test in which certain factors, such as voltage, temperature, and so forth, are increased or decreased beyond normal operating values to obtain observable deterioration in reasonable period of time, and thereby afford some measure of the probable life under normal operating conditions or some measure of the durability of the equipment when exposed to the factors being aggravated.