triangular rule

基本解释

It is proved that a triangular-norm is a rule-union operator;
证明了三角模是规则并算子；
The protractor (3) with a triangular rule is arranged on a board and is fixed on the two sides on the upper part of the compasses through an elastic fixing clip (7).
板面上带有三角尺的量角器（3）通过弹性固定卡（7）固定在圆规的上部两侧。
ip.com
Train diagram is replacing gradually the old ways of train traffic control, which relies mainly on one diagram, one pen, one triangular rule and one ruler via telephone communications.
逐步取代了原有的依靠一张图、一支笔、一块三角板、一块橡皮、通过电话传递信息的调度指挥方式。