com·​plex·​i·​ty | \ kəm-ˈplek-sə-tē How to pronounce complexity (audio) , 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

But for an author so meticulous about the complexity of Middle-Earth, the story can't quite scratch the surface of Tolkien's mostly Boy Scout-like reputation. Darren Orf, Popular Mechanics, "'Tolkien': A Life Where Fantasy Met Reality," 3 May 2019 Lastly, don’t be intimidated by the complexity of this exercise, says Stokes. Jenny Mccoy, SELF, "Strengthen Your Glutes and Thighs With This Lateral Lunge Variation From Celebrity Trainer Kira Stokes," 1 Mar. 2019 Per the Palace, Eugenie's gown was developed layer by layer, from the corset to the complexity of its underskirt and full pleated skirt. Carrie Goldberg, Harper's BAZAAR, "How Princess Eugenie's Wedding Dress Compared to Meghan Markle's–and Kate Middleton's," 12 Oct. 2018 While the service was professional and inviting, and the food was reasonably priced for the complexity of the preparation, the prices of the wines by the glass seemed high and the pours small. Michael Bauer,, "Sorrel off to a stellar start in Pacific Heights," 6 July 2018 They were initially bemused by the complexity of bus timetables, bin collections and—most of all—by the changeable weather. The Economist, "A Welsh town shows Britain a new way to welcome refugees," 5 July 2018 Under such a scenario, James could then have worked out a trade to another team without the complexities of the type of sign-and-trade agreement that now will be required after Sunday's start of NBA free agency. Ira Winderman,, "LeBron James opts out of Cavs deal, seemingly eliminating Heat chances," 29 June 2018 Many other innovators have sought to find solutions to health care costs in the past but have run head on into the complexity of the system. Andrew Joseph, STAT, "Surgeon Atul Gawande selected as CEO of new health care company from Amazon, partners," 20 June 2018 Choosing an agent Is one of the most important decisions for a prospect to make, and a quick entry point into the complexities of the NBA. Rob Mahoney,, "Breakaway: Inside the Life of Future Lottery Pick Mikal Bridges," 15 June 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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Statistics for complexity

Last Updated

9 May 2019

Look-up Popularity

Time Traveler for complexity

The first known use of complexity was in 1661

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More Definitions for complexity



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 How to pronounce complexity (audio) \
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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Comments on complexity

What made you want to look up complexity? Please tell us where you read or heard it (including the quote, if possible).


using a distributed computer network

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