Apeirogon

Apeirogon (regular)
Edges and vertices	∞
Schläfli symbol	{∞}
Coxeter–Dynkin diagrams
Internal angle (degrees)	180°
Dual polygon	Self-dual

In geometry, an apeirogon (from Ancient Greek ἄπειρος apeiros 'infinite, boundless', and γωνία gonia 'angle') or infinite polygon is a polygon with an infinite number of sides. Apeirogons are the rank 2 case of infinite polytopes. In some literature, the term "apeirogon" may refer only to the regular apeirogon, with an infinite dihedral group of symmetries.^[1]