单词directrix
n.: 【数】准线；〈古〉同“directress”
网络: 抛物线的准线；导面
【数学】准线
复数：directrixes
A fixed point whose relationship with a directrix determines a conic section.
焦点一个与准线的关系决定圆锥形状的定点
The directrix line of a conic.
二次曲线的准线。
Select the directrix of the new conic. . .
选择新二次曲线的准线…
New Latin parametrum [a line through the focus and parallel to the directrix of a conic]
现代拉丁语parametrum[通过焦点并与圆锥曲线的准轴线平行的直线]
Developable Surfaces Generated by a Directrix
导线生成的可展曲面
Constructing Directrix for Conic Curve
圆锥曲线准线的几何作图