Definitions of Metrology terms & phrases.
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Part of a scale between any two successive scale marks.
The set of values bounded by the extreme indications on an analogue measuring instrument.
Distance between two successive adjacent scale marks measured along the same line as the scale length.
APEC Sub-committee on Standards and Conformance.
Standard whose value is assigned by comparison with a primary standard of the same quantity.
The international system of units, Le Syst
A unit in the SI system.
Sistema Interamricano de Metrologia, Normalizaci
Slovensky Metrologicky Ustav, the national metrological institute of the Slovak Republic.
Sveriges Provnings- och Forskningsinstitut, the national metrological institute of Sweden.
Modulus of the difference between two limits of a nominal range.
The ability of a measuring instrument to maintain constant its metrological characteristics with time.
See Measuring standard.
"Measure of the unpredictability of a random variable, expressed as the average deviation of a set of data from its arithmetic mean and computed as the positive square root of the variance. Customarily represented by the lower-case Greek letter sigma (σ), it is considered the most useful and important measure of dispersion which has all the essential properties of the variance plus the advantage of being determined in the same units as those of the original data. Also called root mean square (RMS) deviation."
As per the ISO GUM, the standard deviation = the standard uncertainty for the given contributor.
Standard deviation, experimental
Parameters for a series of n measurements of the same measurand, characterises the dispersion of the results and is given by the formula for standard deviation.
Standard Reference Material,
see Reference Material, Certified.
A set of similar material measures or measuring instruments that, through their combined use constitutes one standard called a compound standard.
Standard used as an intermediary to compare standards.
Standard, sometimes specially composed, for use in making comparisons between standards at different locations.
System of measurement units
A number of basic units and derived units defined in accordance with given rules for a given system of values.
System of units
Mean that would result from an infinite number of measurements of the same measurand carried out under repeatability conditions minus a true value of the measurand.