duality: Meaning and Definition of

du•al•i•ty

Pronunciation: (d-al'i-tē, dy-), [key]
— n.
  1. a dual state or quality.
  2. a symmetry within a mathematical system such that a theorem remains valid if certain objects, relations, or operations are interchanged, as the interchange of points and lines in a plane in projective geometry.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.
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