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Synonyms

complexity

American  
[kuhm-plek-si-tee] / kəmˈplɛk sɪ ti /

noun

plural

complexities
  1. the state or quality of being complex; intricacy.

    the complexity of urban life.

  2. something complex.

    the complexities of foreign policy.


complexity British  
/ kəmˈplɛksɪtɪ /

noun

  1. the state or quality of being intricate or complex

  2. something intricate or complex; complication

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

  • intercomplexity noun
  • overcomplexity noun
  • supercomplexity noun

Etymology

Origin of complexity

First recorded in 1715–25; complex + -ity

Explanation

Is the movie simple or does it have lots of plot twists and intricate relationships between characters? If the latter is true, the movie's complexity makes it hard to understand. When you see the word complexity, think of something with a lot of pieces, something not easy to put into words or understand. Things that can have complexity include: the events leading up to the American Civil War, a broth made with many ingredients, your relationship with your parents. Complexity is the opposite of simplicity. When something has a lot of complexity, you say it is complex. When it has very little complexity, it is simple.

Keep Reading on Vocabulary.com

Vocabulary lists containing complexity

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

But experts say staffing requirements are driven by complexity rather than numbers, as more women present with diabetes, obesity, or mental health conditions.

From BBC • Apr. 23, 2026

But factors other than size also influence fees: deal structure, regulatory complexity and strong demand for top-tier bankers with a record of closing major transactions, according to M&A lawyers and researchers.

From The Wall Street Journal • Apr. 22, 2026

The study, "Multi-order complexity spiking neurons enabled by printed MoS2 memristive nanosheet networks," was supported by the National Science Foundation.

From Science Daily • Apr. 18, 2026

“The lack of disclosure and contractual complexity of these arrangements makes it difficult for investors to interpret true economic leverage versus that reported on balance sheet,” Castagno’s team writes.

From Barron's • Apr. 17, 2026

Above all, Faure had the confidence to turn his antipathy towards the many- layered complexity of Wagner’s music dramas into a much purer, emotionally restrained sound.

From "The Story of Music" by Howard Goodall