Parallel

Parallel Curves

Parallel Line Segments

Parallelepiped

Parallelogram

Pencil of Circles

Pencil of Lines

Pentadecagon

Pentagon

Pentahedron

Pentomino

Perimeter

Periodic Tessellation

Perpendicular

Perpendicular Bisector

Perpendicular Line Segments

Perpendicular Lines

Pick’s Theorem

Pierre Herigone (1580-1644)

Plane

Plane Geometric Figure

Plane Quadrilateral

Plane Solid

Plane Surface

Platonic Solid

Polycube

Polygon

Polygon Circumscribed About a Circle

Polygon Inscribed in a Circle

Polygonal Chain

Polyhedral Angle

Polyhedron

Polyhedron Circumscribed About a Sphere

Polyhedron Inscribed in a Sphere

Polyiamond

Polyomino

Pre-Image

Prism

Prismatic Surface

Pyramid

Pyramidal Surface

Pythagoras (c. 580 – c. 495 BCE)

Pythagorean Equation

Pythagorean Triple

Quadrilateral

Radius

Radius of a Circular Cone

Radius of a Circular Cylinder

Radius of a Sphere

Radius of a Torus

Ray

Re-Entrant Angular Sector

Rectangle

Reduction

Reflection in a Cartesian Plane

Reflex Angle

Region In the Plane

Regular Convex Polyhedron

Regular Polygon

Regular Polyhedron

Regular Prism

Regular Pyramid

Regular Solid

Regular Star Polygon

Regular Star Polyhedron

Regular Tessellation

Relationship of Congruence

Relationship of Symmetry

Remote Interior Angle

Reproduction

Rhomb

Rhombohedron

Rhombus

Rhombus-Based Pyramid

Right Circular Cone

Right Circular Cylinder

Right Cone

Right Cylinder

Right Prism

Right Pyramid

Right Rectangular Prism

Right Trapezoid

Right Triangle

Right Triangular Prism

Rotation in a Cartesian Plane

Rotational Symmetry

Ruled Surface

Sagitta

Salient Angular Sector

Scalene

Scalene Polygon

Scalene Triangle

Sector

Segment

Segment of a Curve

Self-Intersecting or Star Quadrilateral

Self-Intersecting Polygon

Semi-Regular Polyhedron

Semi-Regular Tessellation

Semicircle