nonorientable

 

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orientability

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• non-orientable

From non- +‎ orientable.

nonorientable (not comparable)

1. (topology) Not able to be oriented.

   The Möbius strip is a nonorientable surface.

   Through every point of a nonorientable surface there passes a Möbius-like nonorientable strip (with an odd number of half-twists) which is part of that surface.

• orientable