n. 单应

Homography \Ho*mog"ra*phy\, n.
1. That method of spelling in which every sound is
represented by a single character, which indicates that
sound and no other.

2. (Geom.) A relation between two figures, such that to any
point of the one corresponds one and but one point in the
other, and vise versa. Thus, a tangent line rolling on a
circle cuts two fixed tangents of the circle in two sets
of points that are homographic.