A 12-sided shape is called a dodecagon.
All I can tell you is that a 16 sided shape is called a Hexadecagon
Parallelogram
Tetrahaidecahedron
Icosahedron
An eighteen-sided shape is called an octakaidecagon, or octadecagon.
you call a seven sided shape a heptagon.
An 11 sided shape is an Eptogon
A 12-sided shape is called a dodecagon.
A 30 sided shape is called a Triacontagon.
A nine sided shape or polygon is called a nonagon.
A seven sided shape is called a heptagon.
Why not just call it "a 130-sided shape"? because its not called that, spaz.
A five sided geometric shape is called a pentagon.
Well, isn't that just a delightful question? A shape with 118 sides is called a "hectatontagon." Just imagine all the happy little angles and lines creating such a unique and special shape. Remember, there are no mistakes in geometry, just happy little discoveries.
The name of a 18 sided polygon is Octadecagon.
All I can tell you is that a 16 sided shape is called a Hexadecagon