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Geometry Concept List

This is a comprehensive list of 200 concepts for the high school Geometry course.

Concept Labels

  1. Point
  2. Line
  3. Plane
  4. Ray
  5. Line Segment
  6. Angle
  7. Vertex
  8. Collinear Points
  9. Coplanar Points
  10. Intersection
  11. Parallel Lines
  12. Perpendicular Lines
  13. Skew Lines
  14. Inductive Reasoning
  15. Deductive Reasoning
  16. Conjecture
  17. Counterexample
  18. Conditional Statement
  19. Hypothesis
  20. Conclusion
  21. Converse
  22. Inverse
  23. Contrapositive
  24. Biconditional Statement
  25. Postulate
  26. Theorem
  27. Proof
  28. Two-Column Proof
  29. Paragraph Proof
  30. Flow Chart Proof
  31. Indirect Proof
  32. Acute Angle
  33. Right Angle
  34. Obtuse Angle
  35. Straight Angle
  36. Complementary Angles
  37. Supplementary Angles
  38. Adjacent Angles
  39. Vertical Angles
  40. Linear Pair
  41. Angle Bisector
  42. Midpoint
  43. Segment Bisector
  44. Perpendicular Bisector
  45. Distance Formula
  46. Midpoint Formula
  47. Compass Construction
  48. Straightedge Construction
  49. Copying a Segment
  50. Copying an Angle
  51. Bisecting a Segment
  52. Bisecting an Angle
  53. Constructing Perpendiculars
  54. Constructing Parallels
  55. Translation
  56. Rotation
  57. Reflection
  58. Dilation
  59. Rigid Motion
  60. Image
  61. Pre-Image
  62. Composition of Transformations
  63. Congruent Figures
  64. Corresponding Parts
  65. Triangle Congruence
  66. SSS Congruence
  67. SAS Congruence
  68. ASA Congruence
  69. AAS Congruence
  70. HL Congruence
  71. CPCTC
  72. Transversal
  73. Corresponding Angles
  74. Alternate Interior Angles
  75. Alternate Exterior Angles
  76. Same-Side Interior Angles
  77. Parallel Postulate
  78. Slope
  79. Slope-Intercept Form
  80. Point-Slope Form
  81. Equations of Parallel Lines
  82. Equations of Perpendicular Lines
  83. Coordinate Proof
  84. Triangle
  85. Scalene Triangle
  86. Isosceles Triangle
  87. Equilateral Triangle
  88. Acute Triangle
  89. Right Triangle
  90. Obtuse Triangle
  91. Triangle Sum Theorem
  92. Exterior Angle Theorem
  93. Third Angle Theorem
  94. Base Angles Theorem
  95. Triangle Inequality Theorem
  96. Hinge Theorem
  97. Median of a Triangle
  98. Altitude of a Triangle
  99. Perpendicular Bisector Triangle
  100. Angle Bisector of Triangle
  101. Centroid
  102. Orthocenter
  103. Circumcenter
  104. Incenter
  105. Polygon
  106. Regular Polygon
  107. Interior Angles of Polygon
  108. Exterior Angles of Polygon
  109. Quadrilateral
  110. Parallelogram
  111. Rectangle
  112. Rhombus
  113. Square
  114. Trapezoid
  115. Isosceles Trapezoid
  116. Kite
  117. Pentagon
  118. Hexagon
  119. Octagon
  120. Tessellation
  121. Similar Figures
  122. Scale Factor
  123. Similarity Ratio
  124. AA Similarity
  125. SAS Similarity
  126. SSS Similarity
  127. Proportional Segments
  128. Geometric Mean
  129. Altitude to Hypotenuse
  130. Pythagorean Theorem
  131. Pythagorean Triple
  132. Converse Pythagorean Theorem
  133. Distance in Coordinate Plane
  134. Sine Ratio
  135. Cosine Ratio
  136. Tangent Ratio
  137. Inverse Trigonometric Functions
  138. Angle of Elevation
  139. Angle of Depression
  140. Indirect Measurement
  141. Circle
  142. Center of Circle
  143. Radius
  144. Diameter
  145. Chord
  146. Secant
  147. Tangent to Circle
  148. Point of Tangency
  149. Central Angle
  150. Inscribed Angle
  151. Intercepted Arc
  152. Major Arc
  153. Minor Arc
  154. Semicircle
  155. Arc Length
  156. Sector
  157. Segment of Circle
  158. Inscribed Polygon
  159. Circumscribed Polygon
  160. Equation of Circle
  161. Area of Rectangle
  162. Area of Square
  163. Area of Parallelogram
  164. Area of Triangle
  165. Area of Trapezoid
  166. Area of Rhombus
  167. Area of Kite
  168. Area of Regular Polygon
  169. Area of Circle
  170. Circumference
  171. Pi
  172. Perimeter
  173. Prism
  174. Pyramid
  175. Cylinder
  176. Cone
  177. Sphere
  178. Polyhedron
  179. Face
  180. Edge
  181. Lateral Face
  182. Lateral Edge
  183. Base of Solid
  184. Height of Solid
  185. Surface Area
  186. Lateral Surface Area
  187. Volume of Prism
  188. Volume of Pyramid
  189. Volume of Cylinder
  190. Volume of Cone
  191. Volume of Sphere
  192. Cross-Section
  193. Cavalieri's Principle
  194. Net of Solid
  195. Scale Drawing
  196. Scale Model
  197. Optimization Problem
  198. Modeling with Geometry
  199. Design Challenge
  200. Geometric Proof Portfolio