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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.

To answer this, the team examined evidence across four main areas: stone tool production, hunting strategies, symbolic behavior, and social complexity.

From Science Daily • Apr. 12, 2026

To add to the complexity, I am terrified of flying, so we would likely need to book a transatlantic cruise to and from Europe.

From MarketWatch • Apr. 9, 2026

The deals often saddle the merged company with complexity, stagnant brands and crushing debt.

From The Wall Street Journal • Apr. 8, 2026

"Members of the public are understandably frustrated with the situation, as are we, the longevity of it and the complexity of it as well."

From BBC • Apr. 7, 2026

“You want something?” said Gloria, eyes wide in an apparently artless complexity that fooled her huge “nursemaid” not at all.

From "I, Robot" by Isaac Asimov