Adjective

(en adjective)

Referring to a tangent, moving at a tangent to something.

* 2002 , Edward Teller, Memoirs: A Twentieth Century Journey in Science and Politics , page 560

The meteor came in on a tangential orbit and exploded about 8 or 10 miles above the earth's surface, just south of the Arctic Circle.

*{{quote-magazine, date=2012-03

, author=(Henry Petroski) , title=Opening Doors , volume=100, issue=2, page=112-3 , magazine= citation , passage=A doorknob of whatever roundish shape is effectively a continuum of levers, with the axis of the latching mechanism—known as the spindle—being the fulcrum about which the turning takes place. Applying a force tangential to the knob is essentially equivalent to applying one perpendicular to a radial line defining the lever.}}

Merely touching, positioned as a tangent.

* 1898 , Gary Nathan Calkins, Mitosis in ''Noctiluca miliaris'' and its bearing on the nuclear relations of the Protozoa and Metazoa , Ph.D. Thesis, page 3

The archoplasm divides and forms a very large spindle which first lies tangential to the surface of the nucleus.

Only indirectly related.

That subject is tangential to our discussion, and we cannot let it distract us.

Adjective

(-)

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

A chord and the radius that bisects it are orthogonal .

(mathematics)

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

The normal vector and tangent vector at a given point are orthogonal .

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

# Of a linear transformation: preserving its angles.

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

(statistics) Statistically independent, with reference to variates.

(software engineering) Of two or more aspects of a problem, able to be treated separately.

The content of the message should be orthogonal to the means of its delivery.

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