GeezerVison

English

(Received Pronunciation, Standard Southern British) IPA^(key): /ˌkɒmplɪˈmɛnt(ə)ɹi/
- Audio (Berkshire, Standard Southern British): (file)
(General American, Atlantic Canada) enPR: kŏm'plĭ-mĕnʹtə-rē, -trē, IPA^(key): /ˌkɑmplɪˈmɛnt(ə)ɹi/
(Canada, Boston, Maine) IPA^(key): /ˌkɒmplɪˈmɛnt(ə)ɹi/
(Australia) IPA^(key): /ˌkɔmplɪˈment(ə)ɹi/
(New Zealand) IPA^(key): [ˌkɔ̟mpləˈment(ə)ɹi]
Homophone: complimentary
Rhymes: -ɛntəɹi, -ɛntɹi
Hyphenation: com‧ple‧men‧ta‧ry

complementary (comparative more complementary, superlative most complementary)

Acting as a complement; making up a whole with something else.
I'll provide you with some complementary notes to help you study.

The two business partners had complementary abilities: one had excellent people skills, while the other had a head for figures.
- 1988, Andrew Radford, Transformational grammar: a first course, Cambridge, UK: Cambridge University Press, page 140:
  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).
(genetics) Of the specific pairings of the bases in DNA and RNA.
(physics) Pertaining 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.)

Complementary and complimentary are frequently confused and misused in place of one another.

single words

Multiword expressions

acting as a complement

of the specific pairings of the bases in DNA and RNA

complementary (plural complementaries)

A complementary colour.
(obsolete) One skilled in compliments.
- 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:
  the hands of the most skilful and cunning complementaries alive
An angle which adds with another to equal ninety degrees.

a complementary (i.e. colour or angle)