Dictionary · Standards & Units
Quantity of dimension one
A quantity whose dimension has all base-quantity exponents equal to zero — refractive index, strain, a ratio of like quantities; often loosely called "dimensionless".
Related terms
More from Standards & Units
Ordinal quantity-value scale
A quantity-value scale for ordinal quantities, established by agreement on a procedure — comparisons of order are valid, arithmetic on the values is not.
VIM (JCGM 200:2012) 1.28
Conservation of a measurement standard
The set of operations necessary to preserve the metrological properties of a standard within stated limits — storage, handling, surveillance, and use discipline.
VIM (JCGM 200:2012) 5.11
Quantity dimension
The expression of a quantity's dependence on the base quantities as a product of powers of their dimensions — force has dimension L·M·T⁻².
VIM (JCGM 200:2012) 1.7
System of quantities
A set of quantities together with the non-contradictory equations relating them — the framework a system of units is built on.
VIM (JCGM 200:2012) 1.3
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
System of units
A set of base and derived units, with their multiples and submultiples, defined under given rules for a given system of quantities.
VIM (JCGM 200:2012) 1.13