com·plex·i·ty | \kəm-ˈplek-sə-tē, käm-\
plural complexities

Definition of complexity 

1 : something complex the complexities of the murder trial

2 : the quality or state of being complex the complexity of the contract

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Examples of complexity in a Sentence

He was impressed by the complexity of the music. The diagram illustrates the complexity of the cell's structure. He doesn't grasp the complexity of the situation.
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Recent Examples on the Web

As the Trump administration continues to clamp down on immigration policy, stories of the system’s complexities are emerging., "Today: If Roe Vs. Wade Is Overturned," 29 June 2018 That complexity has given the researchers an idea about the evolution into birds in the first place. David Grossman, Popular Mechanics, "Dinosaurs Could Barely Use Their Tongues," 20 June 2018 It's been a challenge and a joy, just the complexities of her. Josh Wigler, The Hollywood Reporter, "'Fear the Walking Dead' Star "Disappointed" to Be Leaving AMC Spinoff," 11 June 2018 Her work continues to present and explore the richness and depth of Appalachian and African heritage in the American South and how those complexities fortify the culture at large. John Adamian,, "Seven Concerts You Might Want To See (And Why)," 9 June 2018 The complexity unfolds in layers and each bite elicits a different impression. Michael Bauer, San Francisco Chronicle, "Gran Electrica in Napa: Mexican cuisine straight outta Brooklyn," 31 May 2018 Both possessed bright red fruit flavors — strawberries, red raspberries, Montmorency cherries — light, forward, juicy and translucent, with textures that emphasize immediacy over complexity. Patrick Comiskey,, "Why you should be drinking Gamay Noir this summer," 11 July 2018 The lurching advances in building complexity match the explosion in her cognitive abilities as one idea connects with another, as plans form, as capabilities are discovered, as the images in her head have edged toward conscious thought. Aaron Gilbreath, Longreads, "The Inward Empire," 27 June 2018 Stage 9 is expected to be a fan favorite because of its complexities. Gina Martinez, Time, "Your Ultimate Guide to the 2018 Tour de France," 6 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'complexity.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of complexity

1661, in the meaning defined at sense 1

History and Etymology for complexity

see complex entry 2

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Last Updated

26 Sep 2018

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Time Traveler for complexity

The first known use of complexity was in 1661

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English Language Learners Definition of complexity

: the quality or state of not being simple : the quality or state of being complex

: a part of something that is complicated or hard to understand


com·plex·i·ty | \kəm-ˈplek-sə-tē \
plural complexities

Kids Definition of complexity

1 : the quality or condition of being difficult to understand or of lacking simplicity the complexity of a problem

2 : something difficult to understand or lacking simplicity the complexities of business

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