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Synonyms

duality

American  
[doo-al-i-tee, dyoo-] / duˈæl ɪ ti, dyu- /

noun

  1. a dual state or quality.

  2. Mathematics. 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.


duality British  
/ djuːˈælɪtɪ /

noun

  1. the state or quality of being two or in two parts; dichotomy

  2. physics the principle that a wave-particle duality exists in microphysics in which wave theory and corpuscular theory are complementary. The propagation of electromagnetic radiation is analysed using wave theory but its interaction with matter is described in terms of photons. The condition of particles such as electrons, neutrons, and atoms is described in terms of de Broglie waves

  3. geometry the interchangeability of the roles of the point and the plane in statements and theorems in projective geometry

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

  • nonduality noun

Etymology

Origin of duality

1350–1400; Middle English dualitie < Late Latin duālitās. See dual, -ity

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Perhaps highlighting how the theme of duality runs deep even within Requiem's team itself, Kawata says how despite this, the team have still brought "something new to the table" with their latest offering.

From BBC • Feb. 27, 2026

Li describes the finding as part of what he calls a "new duality."

From Science Daily • Nov. 9, 2025

Halloween, for all its associations with extremes of terror, is also bound up in the cozy innocence of childhood memories, and to my mind, few movies fit that duality better than “The Fog.”

From The Wall Street Journal • Oct. 29, 2025

Bringing that duality introduced a style that was both fresh and ancestral into a pop music scene still defined by the electronic splash of New Jack Swing artists like Boyz II Men, Saadiq’s group Tony!

From Salon • Oct. 19, 2025

In fact, they had encountered the same wave-particle duality of light that was confounding their elders in physics.

From "Big Science" by Michael Hiltzik