Geometry

2. A flat two-dimensional surface upon which two-dimensional objects (e.g., circle, square) can lie, or the face of a three-dimensional object as it creates a surface (e.g., face of a cube); the dimensions of which are infinite.
4. Without a curve.
8. Figures
9. Two lines that meet to make a corner.
10. A closed figure with three sides.
11. Two lines in a two-dimensional space that do not meet (for example, the opposite sides of a square). A parallelogram has two sets of parallel lines.
14. A specific position on a line, plane, or in space.
15. A two-dimensional shape in which all points on the curved line are equidistant from a center point.
16. Surface planes of three-dimensional shapes.
19. Line segments in geometric figures that compose the exterior of the object.
20. A two-dimensional, closed, four-sided figure with four right angles.

1. Also known as corner/corners. The point at which two sides of a two-dimensional figure or two edges of a three-dimensional figure meet.
3. terms: Words and phrases that describe the location of an object in relation to other objects, including words like on, under, on top of, next to, in front of, behind, beneath, underneath, inside, outside, at/on the bottom/top, between, and adjacent to (this is just a sample, there are many more).
5. Having a plane-like quality.
6. Sides that are the same length.
7. Having curvy or undulating attributes (e.g., ocean, octopus tentacles).
12. A closed four-sided figure with parallel opposite sides. A square is a special kind of rhombus. Sometimes called a diamond.
13. Terminology to describe the dimensions of an object or set. With young children, the terms large, medium, small, taller, shorter, longer, less than and greater than are all appropriate.
15. Identical in size and shape.
17. The meeting of two faces on a three-dimensional shape.
18. An informal word to describe angles of objects.