contravariance

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noun

The reversal of the order of data types acted upon by an operator.

OriginEnglish variance ← Latin contrā ← Proto-Italic *komterād →
Scrabble 21
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Meanings

nouncontravariance (countable and uncountable, plural contravariances)

plural contravariances

  1. countableuncountableobject-oriented programmingThe reversal of the order of data types acted upon by an operator.

    I get why with covariance I can return a Dog (a Dog is a Mammal), but why does contravariance work the other way? Shouldn't it accept a derived type when it expects a base type? Contravariance is consistent with Postel's Law: […]

    2005, Jesse Liberty, Visual C# 2005: A Developer's Notebook, O'Reilly Media, →ISBN, page 47
  2. countableuncountablecategory theoryA functor which reverses composition.
  3. countableuncountablelinear algebraOf vectors, the property of scaling inversely with a change of basis, as opposed to covariance.

Origin

  1. Proto-Indo-European*ḱe?
  2. Proto-Indo-European*ḱóm
  3. Proto-Italic*kom
  4. Proto-Italic*kom-
  5. Proto-Italic*komteros
  6. Proto-Italic*komterād
  7. Latincontrā
  8. Englishcontra-
  9. Englishvariance
  10. Englishcontravariance

From contra- + variance.

Full word history & related roots →

Translations

Chinese Mandarin 逆變 /逆变
  • 逆變 /逆变 (nìbiàn)reversal of the order of data types acted upon by an operator
Finnish kontravarianssi, kontravarianssi
  • kontravarianssireversal of the order of data types acted upon by an operator
  • kontravarianssifunctor which reverses composition
French contravariance
  • contravariancereversal of the order of data types acted upon by an operator
German Kontravarianz, Kofunktor
  • Kontravarianzreversal of the order of data types acted upon by an operator
  • Kofunktorfunctor which reverses composition
Portuguese contravariância
  • contravariânciareversal of the order of data types acted upon by an operator
Romanian contravarianță
  • contravarianțăreversal of the order of data types acted upon by an operator
Russian контравариантность
  • контравариантность (kontravariantnostʹ)reversal of the order of data types acted upon by an operator
Cite this entry
APA

contravariance. (n.d.). In WatkinsX Dictionary. Retrieved November 3, 2026, from https://dictionary.watkinsx.com/word/contravariance

MLA

“contravariance.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/contravariance. Accessed November 3, 2026.

Chicago

WatkinsX Dictionary, s.v. “contravariance,” accessed November 3, 2026, https://dictionary.watkinsx.com/word/contravariance.

Source: contravariance on Wiktionary, CC BY-SA 4.0.