| Answer | Crossword Clue |
|---|---|
| POLYGON | Closed plane figure |
| ELLIPSE | Closed plane curve. |
| ISOGON | Plane figure |
| NONAGON | Plane figure. |
| COPILOT | Plane figure |
| AREA | Plane figure |
| POLYGON | Plane figure. |
| DECAGON | Plane figure |
| CIRCLE | Plane figure |
| GROUNDSPEED | Plane figure? |
| ETA | Plane figure? (abbr.) |
| CIRC | Plane geom. figure |
| TRAPEZIUM | Quadrilateral plane figure |
| LUNE | Figure in plane geometry |
| TRAPEZET | Plane figure in mathematics. |
| QUADRANGLE | Four-pointed plane figure |
