Decagon is a plane geometrical figure of ten sides. When the sides are equal, the figure is called a regular decagon.
Decagon
Chambers's Encyclopaedia, Volume 3: Catarrh to Dion, p. 719
Source scan(s): p. 0730
Decagon is a plane geometrical figure of ten sides. When the sides are equal, the figure is called a regular decagon.