adjoint

A1D2J8O1I1N1T1
/ˈæd͡ʒ.ɔɪnt/

adjective

Used in certain contexts, in each case involving a pair of transformations, one of which is, or is analogous to, conjugation (either inner automorphism or complex conjugation).

Similar

Meanings

adjectiveadjoint (not comparable)
  1. not comparablemathematicsUsed in certain contexts, in each case involving a pair of transformations, one of which is, or is analogous to, conjugation (either inner automorphism or complex conjugation).
  2. not comparablecategory theoryThat is related to another functor by an adjunction.
  3. not comparablegeometryHaving a relationship of the nature of an adjoint (adjoint curve); sharing multiple points with.

    This imposes n(n - 3)/2 conditions on the n-gon adjoint curve.

    2016, Eugene Wachspress, Rational Bases and Generalized Barycentrics: Applications to Finite Elements and Graphics, page 216
    2 more examples

    The sets A + A₀, B + B₀, together, form the complete intersection, with f = 0, of a composite adjoint curve of order m + k, consisting of the adjoint curve of order m through A + B, together with the non-adjoint curve ω = 0; and the set B + B₀ consists of p points, and lies on i + j adjoint φ-curves of f = 0.

    1933, H. F. Baker, Principles of Geometry, volume 5, published 2010, page 103

    As we have stated before, a curve f' is adjoint to a curve f if it have at least the multiplicity r#95;i-1 at each point where f has the multiplicity r#95;i. A first polar #92;sum#95;iy#95;i#92;left(#92;partialf#47;#92;partialx#95;i#92;right)#61;0 is an example of an adjoint curve.

    1963, Julian Lowell Coolidge, A History of Geometrical Methods, page 205
nounadjoint (plural adjoints)

plural adjoints

  1. mathematicsThe transpose of the cofactor matrix of a given square matrix.
  2. linear algebraTranspose conjugate.
  3. mathematical analysisHermitian conjugate.
  4. category theoryA functor related to another functor by an adjunction.
  5. algebraic geometryA curve A such that any point of a given curve C of multiplicity r has multiplicity at least r–1 on A. Sometimes the multiple points of C are required to be ordinary, and if this condition is not satisfied the term sub-adjoint is used.
  6. An assistant to someone who holds a position in the military or civil service.

    . Nominated the citizens Fayolles, captain of infantry, and Favery of the Engineers to be my adjoints, and dispatched the letters of nomination to the Minister at War, so now I am fairly afloat.

    1798, Theobald Wolfe Tone, The Writings of Theobald Wolfe Tone 1763-98, Volume 3
    2 more examples

    Even as it is, by the reckless aggregation of machine-workers and their adjoints in the great cities and the manufacturing districts, it has kept down life amongst us, and keeps it down to a miserably low standard; so low that any standpoint for improvement is hard to think of even.

    1884, William Morris, Art and Socialism

    The chef and his adjoints are seen by this code as part of the military, subject to military jurisdiction despite their obligation to execute the orders of the administrative council and of the justice of the peace.

    1975, Elizabeth L. Saxe, Sidney Wilfred Mintz, Working Papers in Haitian Society and Culture, page 60
  7. An assistant mayor of a French commune.

    Mayors and their adjoints were often simple cultivateurs like the majority of the community.

    1989, Alan Forrest, Conscripts and Deserters, →ISBN
    1 more example

    A vigorous, aggressive, and ambitious mayor will not rely overmuch upon his adjoints, but a mayor of the more passive type will lean heavily upon them.

    1929, Chester Collins Maxey, Urban Democracy, page 89

Synonyms & antonyms

Similar

Origin

  1. Frenchadjoindre“to join”
  2. Englishadjoint

From French adjoindre (“to join”), from late 19th C; see also adjoin. Doublet of adjunct. In the case of category theory (which brings together concepts from numerous fields), the term is often confounded with adjunct and the relationship is called an adjunction. The origin of any particular usage may therefore be uncertain.

Full word history & related roots →

Translations

Bulgarian спрегнат, матрица на адюнгираните количества
  • спрегнат (spregnat)matrix
  • матрица на адюнгираните количества (matrica na adjungiranite količestva)matrix
Esperanto adjunkta
  • adjunktamatrix
Finnish adjungoitu
  • adjungoitumatrix
German adjungiert, Adjungierte
  • adjungiertmatrix
  • Adjungiertematrix
Spanish adjunta, matriz de adjuntos
  • adjuntamatrix
  • matriz de adjuntosmatrix
  • matriz de cofactoresmatrix
Cite this entry
APA

adjoint. (n.d.). In WatkinsX Dictionary. Retrieved November 2, 2026, from https://dictionary.watkinsx.com/word/adjoint

MLA

“adjoint.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/adjoint. Accessed November 2, 2026.

Chicago

WatkinsX Dictionary, s.v. “adjoint,” accessed November 2, 2026, https://dictionary.watkinsx.com/word/adjoint.

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