di.rec.trix
n.（名词）【复数】 di.rec.trix.es 或 di.rec.tri.ces [do.rμk-tro.sôz] Mathematics The fixed curve traversed by a generatrix in generating a conic section or a cylinder.【数学】 准线：穿过产生圆锥部分或圆柱的母线而形成的固定曲线The median line in the trajectory of fire of an artillery piece.中线：一门大炮开火的轨迹中线
