Dictionary · Standards & Units
Secondary measurement standard
A standard established through calibration with respect to a primary standard for a quantity of the same kind.
Related terms
More from Standards & Units
National measurement standard
A standard recognized by national authority to serve, in a state or economy, as the basis for assigning values to other standards of the same kind.
VIM (JCGM 200:2012) 5.3
Off-system measurement unit
A unit that does not belong to the system of units in use — the day, the electronvolt, and the nautical mile relative to the SI.
VIM (JCGM 200:2012) 1.15
Quantity value
A number together with a reference (such as a measurement unit) expressing the magnitude of a quantity — 5.34 m, 0.152 kg, or a value on an agreed scale.
VIM (JCGM 200:2012) 1.19
Derived quantity
A quantity in a system of quantities defined in terms of the base quantities of that system — speed, force, pressure.
VIM (JCGM 200:2012) 1.5
Measurement unit
A real scalar quantity, defined and adopted by convention, with which any other quantity of the same kind is compared to express the ratio of the two quantities as a number.
VIM (JCGM 200:2012) 1.9
Coherent derived unit
A derived unit that is a product of powers of base units with no numerical factor other than one — the newton is coherent in the SI; the kilometre per hour is not.
VIM (JCGM 200:2012) 1.12