じょうぎ定規jougi
1.

A tool used to draw straight lines or curves, often including various types such as triangular, T-shaped, or flexible rulers.

2.

A standard or criterion used to assess or evaluate things, often serving as a basis for judgment.

3.

The quality of being consistent or fixed, indicating something that remains unchanged or follows established norms.

Example:

私は本を買い、彼は定規を買った。

さんかくじょうぎ三角定規sankakujougi
1.

A triangular tool used in drafting and drawing, typically shaped as a right-angled triangle, which ensures accurate angles and straight lines in technical illustrations.

2.

A measuring instrument designed in the form of a triangle, commonly featuring one right angle and often employed in geometry and construction for creating precise angles.

3.

A geometrical aid that comes in various triangular forms, primarily utilized in educational settings to assist in teaching and practicing concepts related to angles and shapes.

しゃくしじょうぎ杓子定規shakushijougiしゃくしshakushiじょうぎ定規jougi
1.

A mindset or approach that adheres rigidly to a fixed standard or set of rules, leaving little room for flexibility or adaptation to varying situations.

2.

An attitude characterized by a strict application of established conventions or guidelines, often resulting in a lack of creativity or openness to change.

3.

A practice of enforcing uniformity based on a single criterion, disregarding the complexities and nuances of individual cases or circumstances.