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.

Measurand

The quantity intended to be measured. Specifying a measurand requires the kind of quantity and a description of the state of the phenomenon, body, or substance carrying it.

VIM (JCGM 200:2012) 2.3 · General

Measured quantity value

The quantity value representing a measurement result — the value actually obtained for the measurand in a given measurement.

VIM (JCGM 200:2012) 2.10 · General

Measurement

The process of experimentally obtaining one or more quantity values that can reasonably be attributed to a quantity, presupposing a description of the quantity, a procedure, and calibrated equipment.

VIM (JCGM 200:2012) 2.1 · General

Measurement accuracy

Closeness of agreement between a measured value and a true value of the measurand. A qualitative concept — a measurement is more accurate when it offers smaller error, but accuracy itself is not a number.

VIM (JCGM 200:2012) 2.13 · General

Measurement error

Measured quantity value minus a reference quantity value; comprises a systematic component and a random component.

VIM (JCGM 200:2012) 2.16 · General

Measurement method

A generic description of the logical organization of operations used in a measurement — substitution method, differential method, null method.

VIM (JCGM 200:2012) 2.5 · General

Measurement principle

The phenomenon serving as the basis of a measurement — thermoelectric effect for a thermocouple, Doppler shift for a radar gun.

VIM (JCGM 200:2012) 2.4 · General

Measurement procedure

A detailed description of a measurement according to a principle and method, based on a measurement model — detailed enough that a trained operator can perform it. The SOP is its documented form.

VIM (JCGM 200:2012) 2.6 · General

Measurement result

The set of quantity values attributed to a measurand together with any other available relevant information — generally a measured value with its measurement uncertainty.

VIM (JCGM 200:2012) 2.9 · General

Metrology

The science of measurement and its application — including all theoretical and practical aspects, whatever the uncertainty and field of application.

VIM (JCGM 200:2012) 2.2 · General