| Definition | Word |
| type of figure that has both a starting point and an endpoint | |
| type of figure that continues on on both directions forever | |
| two angles that add to 180 degrees | |
| two angles that add to 90 degrees | |
| the name for a pair of angles that form a line | |
| the number of degrees in a circle | |
| the number of sides on a pentagon | |
| a figure that 'caves' inside itself | |
| type of polygon that has all equal angles and side lengths | |
| type of triangle that has three different side lengths | |