Definition of "orthogonality"

In this chapter we develop one of the key concepts in the geometry of the vector space Rn, namely, the concept of orthogonality of vectors.

1984, John Wesley Brown, Donald R. Sherbert, Introductory Linear Algebra with Applications, Prindle Weber & Schmidt

Suppose we have an imaginary pair of axes with a set of comparable language entities on one and a set of attributes or capabilities on the other. When we talk of “orthogonality”, we usually mean that the space defined by these axes is as “full” as we can logically make it. Part of the Ruby way is to strive for this orthogonality.

2015, Hal Fulton, André Arko, The Ruby Way […] , Addison-Wesley Professional, page xl