Rational Number

Re-Entrant Angle

Rectangle

Reflection

Regular Polygon

Rhombus

Right Angle

Right Triangle

Rotation in a Plane

Salient Angle

Scalene Triangle

Segment

Segment of a Curve

Simple Curve

Simplified Fraction

Solid

Square

Square of a Number

Square Root of a Real Number

Straight Angle

Straight Line

Subtraction

Subtraction Equation

Surface Area of a Solid

Survey

Symmetric Figure

Tessellation

Tiling

Trapezoid

Triangle

Triangular Number

Unit of Measurement of Space

Unit of Measurement of Surface Area

Volume

Whole Number

Zero Angle