Knowledge
Metrology Dictionary
The complete VIM vocabulary — all numbered concepts of JCGM 200:2012 as faithful paraphrases with clause citations — plus clearly labeled practice terms from the GUM, ILAC, ISO and NIST guidance.
Random measurement error
The component of measurement error that varies unpredictably in replicate measurements, characterized by a distribution usually summarized by its standard deviation.
VIM (JCGM 200:2012) 2.19 · General
Range of a nominal indication interval
The absolute difference between the extreme values of a nominal indication interval — 200 V for the −100 V to +100 V setting.
VIM (JCGM 200:2012) 4.5 · Instruments
Rated operating condition
An operating condition that must be fulfilled during measurement for an instrument to perform as designed — the environmental and use envelope the specs assume.
VIM (JCGM 200:2012) 4.9 · Instruments
Reference data
Data related to a property of a phenomenon, body, or substance — or to a system of components of known composition or structure — obtained from an identified source, critically evaluated, and verified for accuracy.
VIM (JCGM 200:2012) 5.16 · Standards & Units
Reference material
Material, sufficiently homogeneous and stable with reference to specified properties, established to be fit for its intended use in measurement or in examination of nominal properties.
VIM (JCGM 200:2012) 5.13 · Standards & Units
Reference measurement procedure
A procedure accepted as providing results fit for assessing the trueness of values obtained from other procedures for the same kind of quantity.
VIM (JCGM 200:2012) 2.7 · General
Reference measurement standard
A standard designated for the calibration of other standards for quantities of a given kind in an organization or at a location — a laboratory's best standard.
VIM (JCGM 200:2012) 5.6 · Standards & Units
Reference operating condition
An operating condition prescribed for evaluating the performance of an instrument or for comparing results — the 23 °C ± 1 °C line at the top of a datasheet.
VIM (JCGM 200:2012) 4.11 · Instruments
Reference quantity value
A quantity value used as a basis for comparison with values of quantities of the same kind — a true value, a conventional value, or a standard's certified value, depending on context.
VIM (JCGM 200:2012) 5.18 · Standards & Units
Relative standard measurement uncertainty
A standard uncertainty divided by the absolute value of the measured quantity value — the form specifications and CMCs often quote (parts in 10⁶, percent of reading).
VIM (JCGM 200:2012) 2.32 · Uncertainty
Repeatability condition of measurement
A condition set that includes the same procedure, operators, measuring system, operating conditions, and location, with replicates over a short period.
VIM (JCGM 200:2012) 2.20 · Statistics
Reproducibility condition of measurement
A condition set that includes different locations, operators, and measuring systems applying the same procedure to the same or similar objects.
VIM (JCGM 200:2012) 2.24 · Statistics
Resolution
The smallest change in the quantity being measured that causes a perceptible change in the corresponding indication. Digital resolution contributes a rectangular uncertainty component of (δ/2)/√3.
VIM (JCGM 200:2012) 4.14 · Instruments
Resolution of a displaying device
The smallest difference between displayed indications that can be meaningfully distinguished — for a digital display, one count of the least significant digit.
VIM (JCGM 200:2012) 4.15 · Instruments