Definition of "orthogonal"

(geometry) Of two objects, at right angles; perpendicular to each other.  examples

(mathematics)

1. Of a pair of vectors: having a zero inner product; perpendicular.  examples

2. Of a square matrix: such that its transpose is equal to its inverse.  examples

3. Of a linear transformation: preserving its angles.  examples

4. Of grid graphs, board games and polyominoes: vertical or horizontal but not diagonal.  examples

5. Of a pair of elements in an ortholattice: each less than or equal to the orthocomplement of the other.  examples

(statistics) Statistically independent, with reference to variates.  examples

(software engineering) Of two or more aspects of a problem, able to be treated separately; of a design, exhibiting consistency and composability.  quotations  examples

Of two or more problems or subjects, independent of or irrelevant to each other.  examples

An orthogonal line  examples