1.
set square; triangle ruler
A triangular drafting tool used for drawing straight lines and angles. In Japan, students typically use a set of two: one with 30-60-90 degree angles and one with 45-45-90 degree angles.
三角定規で線を引いた。
I drew a line with a set square.
算数の授業で三角定規の使い方を習った。
We learned how to use a set square in math class.
二種類の三角定規を組み合わせると、いろいろな角度の線が引ける。
By combining two types of set squares, you can draw lines at various angles.
USAGE:
A standard school supply in Japan. Elementary school students learn to use set squares in arithmetic class. The two standard types are the 30-60-90 triangle and the 45-45-90 triangle. Part of the standard stationery set alongside a ruler (定規), compass (コンパス), and protractor (分度器).
COMMON COLLOCATIONS:
- 三角定規で角度を測る (to measure angles with a set square)
- 三角定規のセット (a set of triangle rulers)