conjugate directions

conjugate directions

[′kän·jə·gət di′rek·shənz]
(mathematics)
For a point on a surface, a pair of directions, one of which is the direction of a curve on the surface through the point, while the other is the direction of the characteristic of the planes tangent to the surface at points on the curve.
References in periodicals archive ?
It must be noted that principal directions of a tensor are also conjugate directions.
upsilon]] (ray velocity) are a triad of conjugate directions with respect to the inverse relative dielectric permittivity tensor and constitutes a local basis, whose reciprocal one is formed by directions of [bar.