What does orthogonal mean?
Orthogonal describes two lines, axes, or other geometric elements that meet at right angles. The word is especially important in mathematics, physics, and engineering, where orthogonal coordinates, projections, and directions allow complex relationships to be analyzed through perpendicular components. It also has a broader figurative meaning: two subjects or considerations can be described as orthogonal when they are independent or do not directly affect one another. For example, a product’s pricing and its visual design might be treated as orthogonal issues during an early planning discussion, although later decisions could make them related. The term is formal and technical, and it does not simply mean unimportant or unrelated. Its distinctive core idea is perpendicularity, extended metaphorically to describe a complete lack of overlap or interaction between separate systems.
adjectiveAt right angles; perpendicular. In extended use, orthogonal describes things that are independent, unrelated, or not directly relevant to one another.
- At right angles; perpendicular.
- Independent or not directly related, especially in systems, methods, or lines of inquiry.
- Having zero statistical correlation, especially in relation to variables or components.
"The engineer adjusted the second beam so that it was orthogonal to the first."
"The two axes are orthogonal, so a movement along one does not affect the other."
"The committee considered hiring and technology orthogonal issues, even though they would eventually need to be coordinated."
In mathematics, orthogonal lines meet at a right angle; in everyday argument, orthogonal ideas meet at no angle at all because they do not overlap.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does orthogonal come from?
Orthogonal comes from the Greek orthogonios, meaning “right-angled,” formed from orthos, “straight” or “right,” and gonia, an angle. The word entered English through mathematical usage in the seventeenth century. Its Greek root is also reflected in English words such as orthodoxy, orthography, and orthodox, all of which involve the notion of straightness, correctness, or rightness.
Related word forms
How orthogonal is actually used
The mathematical sense is formal and technical. The figurative sense, meaning independent or unrelated, is common in technical, academic, and business writing, where it may imply that two subjects do not interact rather than that they have no connection whatsoever.
Easily confused with orthogonal
Orthogonal means at right angles or unrelated, whereas orthonormal additionally means having unit length, as in an orthonormal basis.