Government can be defined as the political means of creating and enforcing laws; typically via a bureaucratic hierarchy.

The algebraic operations on are defined via these maps in the obvious manner.

Primary standards are defined via other quantities like length, mass and time.

Thus time is defined via measurement - by its standard time interval.

Thus, similar to the definition of other fundamental quantities (like time and mass), space is defined via measurement.

The border between these conditions is sometimes defined via a circle of confusion criterion.

Both of these facts are more generally true for any integral transform defined via convolution.

The relative strength of two systems of formal logic can be defined via model theory.

Composition is defined via compatible representatives as in the pair groupoid.

Both are defined via Taylor series analogous to the real case.