- the axis of a hyperbola perpendicular to the transverse axis at a point equidistant from the foci.
- the segment of this axis equal to one side of a rectangle that has its other side equal to the transverse axis and diagonals that are along the asymptotes of the hyperbola.
Origin of conjugate axis
First recorded in 1875–80
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018