Types of 2D Polygon Shape Names with Sides and Pictures

Polygons are 2D shapes that have a certain number of sides. Their sides are simply joined by straight lines. Another thing to note is that polygons do not have holes, nor do they intersect with themselves. As for the number of sides, they could go on for infinity. 

Polygons with sides 1-10 such as triangle, square, pentagon, hexagon, heptagon, octagon, nonagon and decagon are well known but when number of sides get larger the naming becomes complicated and therefore, we follow a naming convention.

These all are regular polygons in which all angles are equal in measure and all sides have the same length. Regular polygons may be either convex or star. 

Let’s have a look at the list of all polygon names and know what they are called.

2D Polygon Shapes 1-100 with Sides and Pictures

Following is a list of polygons 1-100 and their names with the number of sides they have and an example picture.

Name of PolygonNumber of SidesPicture
Trigon/ triangleThree – 3
Tetragon/ quadrilateral/ rectangle/ parallelogram/ square/ rhombusFour – 4
PentagonFive – 5
HexagonSix – 6
HeptagonSeven – 7
Octagon Eight – 8
Nonagon/enneagonNine – 9
Decagon Ten – 10
HendecagonEleven – 11
DodecagonTwelve – 12
TriskaidecagonThirteen – 13
Tetradecagon Fourteen – 14
Pentadecagon Fifteen – 15
Hexadecagon Sixteen – 16
Heptadecagon Seventeen – 17
Octadecagon Eighteen – 18
Nonadecagon Nineteen – 19
IcosagonTwenty – 20
Icosikaihenagon Twenty one – 21
Icosikaidigon Twenty two – 22
Icosikaitrigon Twenty three – 23 
IcosikaitetragonTwenty four – 24
IcosikaipentagonTwenty five – 25
IcosikaihexagonTwenty six – 26
IcosikaiheptagonTwenty seven – 27
IcosikaioctagonTwenty eight – 28
IcosikainonagonTwenty nine – 29
TriacontagonThirty – 30
TriacontahenagonThirty one – 31
TriacontakaidigonThirty two – 32
TriacontakaitrigonThirty three – 33
TriacontakaitetragonThirty four – 34
TriacontakaipentagonThirty five – 35
TriacontakaihexagonThirty six – 36
TriacontakaiheptagonThirty seven – 37
TriacontakaioctagonThirty eight – 38
TriacontakainonagonThirty nine – 39
TetracontagonForty – 40
TetracontakaihenagonForty one – 41
TetracontakaidigonForty two – 42
TetracontakaitrigonForty three – 43
TetracontakaitetragonForty four – 44
TetracontakaipentagonForty five – 45
TetracontakaihexagonForty six – 46
TetracontakaiheptagonForty seven – 47
TetracontakaioctagonForty eight – 48
TetracontakainonagonForty nine – 49
PentacontagonFifty – 50
HexacontagonSixty – 60
HeptacontagonSeventy – 70
OctacontagonEighty – 80
NonacontagonNinety – 90
NonacontakaihenagonNinety one – 91
NonacontakaidigonNinety two – 92
NonacontakaitrigonNinety three – 93
NonacontakaitetragonNinety four – 94
NonacontakaipentagonNinety five – 95
NonacontakaihexagonNinety six – 96
NonacontakaiheptagonNinety seven – 97
NonacontakaioctagonNinety eight – 98
NonacontakainonagonNinety nine – 99
Hectogon One hundred – 100
360-gonThree hundred and sixty – 360
ChiliagonOne thousand – 1000

How to name a Polygon with N-sides?

As for their names, polygons have very straightforward names for the first ten or twenty names. They use a basic prefix naming system. Di, tri, tetra, penta, and so on. We are familiar with these prefixes as they are used in a variety of mathematical—and even scientific—subjects. But polygons with 21-99 sides have a different naming system. First, we use a prefix for the tens (such as triaconta—30). Then we use a prefix for the ones (such as di—20). At last, we put them together with a ‘kai’ between them. This would be formatted to look like (tens)kai(ones)gon. And for the sake of an example, we have (triaconta)kai(di)gon. In simpler words, a 32-sided polygon. We can normally refer to it as a 32-gon.

When you think of a polygon, you may think of basic shapes you may have learned of in school. A square, a rectangle—maybe even a parallelogram. But have you ever heard of a hectogon? What about a nonahectanonacontakaiheptagon? You probably might not have even read the whole word. This is the name for a polygon with 997 sides. Or, you could simply call it a 997-gon. This is how we classify the more complicated names. They are written as a variable: n-gon. You can replace the with any number you like!

Remember that polygons start at only three sides but can go on for infinity. There is no limit to how many sides a polygon can have! How cool is that?

Looking at the pictures, you may have also noticed that with every added side, the polygon starts to look more and more like a circle. How interesting is it to know that it would never quite become a perfect circle? 

Keep exploring EnglishBix to learn more about math vocabulary words for school kids.

Quick Links

  1. Geometry Vocabulary Words for Beginners
  2. Math Vocabulary Words for Kids
  3. Examples of Prefixes and Suffixes
  4. Circle Words with Meanings

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