Common Core Math Vocabulary

Shape - Definition with Examples

What is a Shape?

Shape Definition: A shape is a figure or surface area enclosed by a boundary. For example; circle, triangle, rectangle etc.

All shapes


Shapes Around Us

The things like clock, money, chessboard, signboard etc. which we come across in everyday life are examples of different shapes.

Real time example of shapes


Types of Shapes

Geometric shapes are classified according to the number of dimensions they exhibit.

Two-Dimensional Shapes:

The shapes that exhibit only two dimensions (height and width) are known as 2D shapes or two-dimensional shapes.

Three-Dimensional Shapes:

The shapes that exhibit three dimensions (height, width and depth) are known as 3D shapes or three-dimensional shapes.

2D Shape      3D Shape


A list of basic geometric shapes along with names and pictures taught to kids in elementary math is given below.

2D Shapes List

3D Shapes List


Open and Closed Shapes

The shapes can be open or closed. They can be formed by curved lines or straight lines.

Open Shapes:

The shapes that have at least one line segment which is not connected to any other line segment at one of its end point are known as open shapes.

Closed Shapes:

The shapes that have all its line segments connected at both end points are known as closed shapes.

Open Shape      Closed Shape


Attributes of Geometric Shapes

The attributes of the shapes make them similar or different. Example, a shape with 3 sides is called a triangle whereas a shape with 5 sides is called a pentagon.

The defining attributes do not change for a shape whereas non-defining may change.

Non Defining Attributes of Shapes     Defining Attribute of Shape


Dimensions of Geometric Shapes

Point - 0 Dimensional


A point is zero-dimensional as it has no dimension (no length, height or width).

Line - 1 Dimensional


A line segment/line is one-dimensional as its length is measured only in one direction. A line segment begins with a point.

Plane - 2 Dimensional


Flat figures drawn on a plane whose lengths are measured in two directions (height and width) are called two-dimensional shapes. For example; rectangle, circle, triangle etc. Two-dimensional shapes are formed by combination of line segments and/or curves.

Solids - 3 Dimensional


Solids with three dimensions (height, depth and length) are called three-dimensional figures. For example, cube, cuboid, prism etc. Three-dimensional shapes are formed by combinations of 2D-faces.


The Complete K-5 Math Learning Program Built for Your Child

More than 20 Million kids love Splash Math