A one-sided topological surface having no inside or outside. It is depicted in ordinary space by inserting the small open end of a tapered tube through the side of the tube and making it contiguous with the larger open end, although a true Klein bottle would not intersect itself.
Origin of Klein bottle
After Felix Klein (1849-1925), German mathematician
Klein bottle. (n.d.). In YourDictionary. Retrieved from https://www.yourdictionary.com/klein-bottle
A smooth surface that has no inside or outside. It is often pictured in ordinary space as a tube that bends back upon itself, entering through the side and joining with the open end. A true Klein bottle, which cannot be constructed in ordinary three-dimensional space, would not actually intersect itself. The Klein bottle is named after the German mathematician Felix Klein (1849–1925).