noun
- semicircular instruments used for measuring and drawing angles
Usage: geometry; mathematics
Examples
- Students used protractors to measure the angles in their triangles.
- The geometry teacher handed out protractors for the angle construction activity.
- Make sure your protractors are clean so you can see the degree markings clearly.
- We need protractors to draw accurate 60-degree angles.
- The protractors in the math kit are made of clear plastic.
- Place the protractors carefully on the vertex of each angle to measure it.