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from Wiktionary, Creative Commons Attribution/Share-Alike License

  • n. The closed manifold obtained by identifying the boundary components of the annulus so that the resultant surface is nonorientable.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • n. a closed surface with only one side; formed by passing one end of a tube through the side of the tube and joining it with the other end


Named after German mathematician Felix Klein (1849-1925) who first described such a surface in 1882. Bottle seems to have come from a misreading or mistranslation of German Fläche ("surface") as Flasche ("bottle"). (Wiktionary)


Sorry, no example sentences found.


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