duality

[doo-al-i-tee, dyoo-]

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

/ 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

Other Word Forms

• nonduality noun

Word History and Origins

Origin of duality¹

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

Example Sentences

Sweeney’s observations about this duality, as seen through O’Brien’s characters, dilute the romanticized notion that having an identical double shields a person from isolation.

From Los Angeles Times

It’s the first offering from his debut EP, “Gemini” — “It’s about the duality of my music, I can’t be put into a box,” he says — which is set for a Sept. 19 release.

From Los Angeles Times

But is that duality of reaping the business benefits while pushing on the human rights transgressions, even possible?

From BBC

Sunday epitomized the duality of the Dodgers’ first 97 games.

From Los Angeles Times

The duality and double entendres in hip-hop is so important and crucial.

From Los Angeles Times

Related Words

• artifice 
• chicanery 
• deceit 
• dishonesty 
• falsehood 
• hypocrisy