The name of a 23 sided shape is an icosikaidigon.
I hate to tell you but this is not true the real answer is Icosikaitri....
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The name of a 12 sided polygon is Dodecagon.
A 8 sided polygon is called a octagon.
The name of a 99 sided polygon is enneacontaenneagon.
The name of a 19 sided polygon is enneadecagon.
The name of a 15 sided polygon is Pentadecagon.
a 23 sided polygon
tricosagon
The name of a 12 sided polygon is Dodecagon.
A 8 sided polygon is called a octagon.
name of 4000 sided polygon
The name of a 18 sided polygon is Octadecagon.
The name of a 99 sided polygon is enneacontaenneagon.
The name of a 8 sided polygon is Octagon.
The name of a 19 sided polygon is enneadecagon.
The name of a 15 sided polygon is Pentadecagon.
The name of a 7 sided polygon is Heptagon.
The name of a 9 sided polygon is Nonagon.