ENGLISH
REFERENCE

complementary

adj. · n.
US //ˌkɑmpɫəˈmɛntɹi// UK //kˌɒmplɪmˈɛntəɹi// com·ple·men·tary
  1. 1 completing each other (adj.)
    B2 Upper Intermediate

    describing two things that work well together because they each provide what the other is missing.

    acting as a complement; completing a whole or enhancing the qualities of another through contrast or addition.

    Example

    The two sisters have very different but complementary personalities.

    Example

    The merger was successful because the two companies possessed complementary strengths in manufacturing and digital marketing.

    Usage

    Often used with the preposition 'to'.
    Pitfall
    The manager gave me a complementary ticket.
    The manager gave me a complimentary ticket.

    Use 'complementary' for things that complete each other. Use 'complimentary' for things that are free or involve praise.

  2. 2 genetics (adj.)
    C1 Advanced Technical Science

    describing how parts of DNA or RNA fit together perfectly like a puzzle.

    relating to the specific pairing of nitrogenous bases in DNA and RNA molecules.

    Example

    In DNA, the base adenine is always complementary to thymine.

    Example

    The double-helix structure relies on complementary base pairing to ensure that genetic information is copied accurately during replication.

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  1. 3 opposite colours (n.)
    B2 Upper Intermediate

    one of two colours that look very different but look good together, like red and green.

    one of a pair of primary or secondary colours that, when combined, create a neutral colour like grey or white.

    Example

    She chose orange as a complementary to the blue walls of the room.

    Example

    The artist used a vibrant purple as a complementary to the yellow highlights, creating a sense of visual tension in the portrait.
  2. 4 geometry (n.)
    C1 Advanced Technical Math

    an angle that, when added to another angle, makes exactly 90 degrees.

    an angle that adds with another to equal 90 degrees or a right angle.

    Example

    If one angle is 30 degrees, its complementary is 60 degrees.

    Example

    The architect calculated the complementary of the roof's pitch to ensure the support beams met at a perfect right angle.

Origin

From complement + -ary. Piecewise doublet of complimentary.

Word family
  • Nouncolor
  • Adjectivecomplementary

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