complementary

kom-pluh-MEN-tree /ˌkɒm.plɪˈmɛn.tər.i/
adjectiveB2GRESATIELTS
AcademicProfessional

Combining in such a way as to enhance or emphasize the qualities of each other; forming a complete whole.

Describes a relationship between two items or skills where each supplies what the other lacks.

The story behind the word. Formed in the 17th century from 'complement' + '-ary', this adjective originally described mathematical angles that add up to 90 degrees (a complete right angle) before expanding into general aesthetics and interpersonal relationships.

Word relationships

  • harmonious: 'Harmonious' implies general agreement, while 'complementary' specifically implies filling mutual gaps.
  • supplementary: 'Supplementary' adds extra material, while 'complementary' implies a balanced, mutual fit.
  • conflicting: 'Conflicting' items clash, whereas 'complementary' items fit together.

Commonly confused with

  • complimentary: 'Complementary' means completion/harmony; 'complimentary' means praising or free of charge.

Word family

  • complement (noun/verb): That which completes; to complete.

Collocations

  • complementary skills
  • complementary colors
  • complementary roles

Example sentences

  • "The two co-founders had complementary skills: one was a brilliant engineer, while the other was a master marketer." Business management
  • "Blue and orange are complementary colors that create striking visual contrast when placed side by side." Art theory

Memory hook

Look at the 'E's: ComplEmentary angles make a complEte right angle. ComplEmentary elements fit together.

When not to use

Do not use to mean free of charge or expressing praise; use 'complimentary'.

Fun facts

  • In medicine, 'complementary medicine' refers to non-mainstream practices used alongside standard medical treatments to form a complete care plan.
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