Dictionary · Standards & Units
Unit equation
A mathematical relation between base and derived units — N = kg·m·s⁻².
Related terms
More from Standards & Units
Certified reference material (CRM)
A reference material accompanied by documentation issued by an authoritative body providing property values with uncertainties and traceability using valid procedures — per ISO 17034 practice.
VIM (JCGM 200:2012) 5.14
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
Submultiple of a unit
A unit obtained by dividing a given unit by an integer greater than one — the millimetre from the metre.
VIM (JCGM 200:2012) 1.18
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
Working measurement standard
A standard used routinely to calibrate or verify instruments or systems, itself usually calibrated against a reference standard.
VIM (JCGM 200:2012) 5.7
Quantity calculus
The set of mathematical rules applied to quantities rather than bare numbers — the algebra by which units propagate through equations.
VIM (JCGM 200:2012) 1.21