complementary

com·ple·men·ta·ry
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UK/ˌkɒmplɪˈmɛnt(ə)ɹi/Atlantic Canada, US/ˌkɑmplɪˈmɛnt(ə)ɹi/

adjective

Acting as a complement; making up a whole with something else.

“I'll provide you with some complementary notes to help you study.”

CommonScrabble 24

Meanings

adjectivecomplementary (comparative more complementary, superlative most complementary)

comparative more complementary · superlative most complementary

  1. Acting as a complement; making up a whole with something else.

    I'll provide you with some complementary notes to help you study.

    2 more examples

    The two business partners had complementary abilities: one had excellent people skills, while the other had a head for figures.

    Using the terminology we introduced earlier, we might then say that black and white squares are in complementary distribution on a chessboard. By this we mean two things: firstly, black squares and white squares occupy different positions on the board: and secondly, the black and white squares complement each other in the sense that the black squares together with the white squares comprise the total set of 64 squares found on the board (i.e. there is no square on the board which is not either black or white).

    1988, Andrew Radford, Transformational grammar: a first course, Cambridge, UK: Cambridge University Press, page 140
  2. biologyOf the specific pairings of the bases in DNA and RNA.
  3. natural sciencesPertaining to pairs of properties in quantum mechanics that are inversely related to each other, such as speed and position, or energy and time. (See also Heisenberg uncertainty principle.)
nouncomplementary (plural complementaries)

plural complementaries

  1. obsoleteOne skilled in compliments.

    the hands of the most skilful and cunning complementaries alive

    1600 (first performance), Beniamin Ionson [i.e., Ben Jonson], “Cynthias Reuels, or The Fountayne of Selfe-Loue. […]”, in The Workes of Beniamin Ionson (First Folio), London: […] Will[iam] Stansby, published 1616, →OCLC
  2. An angle which adds with another to equal ninety degrees.

Synonyms & antonyms

adjectiveof words or propositions so related that each is the negation of the other

Similar

adjectiveacting as or providing a complement (something that completes the whole)

nouneither one of two chromatic colors that when mixed together give white (in the case of lights) or grey (in the case of pigments)

Broader
chromatic colorchromatic colourspectral color

Synonym sets from Open English WordNet, CC BY 4.0.

Origin

Translations

Bulgarian допълнителен
  • допълнителен (dopălnitelen)acting as a complement
Catalan complementari
  • complementariacting as a complement
Dutch aanvullend, complementair
  • aanvullendacting as a complement
  • complementairacting as a complement
Esperanto komplementa
  • komplementaacting as a complement
Finnish täydentävä, komplementaarinen
  • täydentäväacting as a complement
  • komplementaarinenacting as a complement
French complémentaire
  • complémentaireacting as a complement
German komplementär, ergänzend
  • komplementäracting as a complement
  • ergänzendacting as a complement
  • sich ergänzendacting as a complement
  • sich gegenseitig ergänzendacting as a complement
  • einander ergänzendacting as a complement
  • Komplementär-acting as a complement
  • Ergänzungs-acting as a complement
  • Komplement-acting as a complement
  • Zusatz-acting as a complement
  • Gegen-acting as a complement
  • Neben-acting as a complement
  • Ausgleichs-acting as a complement
  • Komplementära complementary (i.e. colour or angle)
  • Ergänzunga complementary (i.e. colour or angle)
Hungarian kiegészítő, komplementer
  • kiegészítőacting as a complement
  • komplementeracting as a complement
Indonesian komplementer
  • komplementeracting as a complement
Latin complēmentārius
  • complēmentāriusacting as a complement
Polish komplementarny, komplementarny
  • komplementarnyacting as a complement
  • komplementarnyof the specific pairings of the bases in DNA and RNA
  • dopełnieniea complementary (i.e. colour or angle)
Portuguese complementar, complementário
  • complementaracting as a complement
  • complementárioacting as a complement
Romanian complementar
  • complementaracting as a complement
Russian дополняющий
  • дополняющий (dopolnjajuščij)acting as a complement
Spanish complementario
  • complementarioacting as a complement
Swedish komplementär, fullständigande
  • komplementäracting as a complement
  • fullständigandeacting as a complement

Rhymes & wordplay

Rhymes with complementary

All rhymes →

Sounds the same

Cite this entry
APA

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

MLA

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

Chicago

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

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