| Acute Triangle | All angles in the triangle are less than 90 degrees. |
| Obtuse Triangle | A triangle where one angle measures over 90 degrees. |
| Right Triangle | One angle in the triangle measures exactly 90 degrees. |
| Isosceles Triangle | A triangle with at least 2 congruent sides |
| Equilateral Triangle | All the sides of the triangle are equal in length |
| Scalene triangle | No equal sides |
| Kite | Quadrilateral with 2 pairs of adjacent congruent sides, with perpendicular diagnals |
| Square | A quadrilateral with 4 sides that are equal and has all 90 degree angles |
| Rhombus | A quadrilateral, all 4 sides the same length |
| Trapezoid hd | Quadrilateral in which exactly 1 pair of parallel sides |
| Trapezoid bd | A quadrilateral with at least 1 pair of parallel sides |
| Rectangle | A quadrilateral in which the opposite sides are parallel, all angles are 90 degrees |
| Parallelogram | Quadrilateral in which the opposite sides are parallel |
| Sphere | All points in a space that are a fixed distance away from a fixed poit |
| Circle | An infinite number of points connected around an equal distance from a middle point` |
| Polyhedron | (The plural is polyhedra) A three dimensional object whose surfaces are composed of polygonal regions (faces, verices, edges) |
| Convex polyhedron | is defined in a manner similar to that used in defining a convex polygon |
| Concave polyhedron | Is defined in a manner similar to that used in defining a concave polygon. |
| Convex Polyhedron | is defined in a manner similar to that used in defining a convex polygon |
| prism | a polyhedron that has two parallel faces that are congruent. These 2 faces are called the bases of the prism. The other faces of the prism are called the lateral faces. (right prism, oblique prism) |
| Pyramid | A polyhedron whose base is a polygon ad whose faces are triangles that have a common vertex. That common vertex is called the apex of the pyramid. |
| Regular Polyhedron | A convex polyhedron in which the faces are congruent regular polygons and in which the number of edges that meet at each vertex are the same. |
| Cylinder | A simple closed surface that is bounded by two congruent simple closed surfaces that lie in the parallel plane |
| Cone | A siple closed surface whose base is a simple closed surface and whose lateral surfaces slopes up to a vertex that is called the apex |
| Sphere | The set of all points in a three dimensional space that are the same distance from a fixed point, called the center |