complexity

noun

com·​plex·​i·​ty kəm-ˈplek-sə-tē 

käm-

plural complexities

1

: something complex

the complexities of the murder trial

2

: the quality or state of being complex

the complexity of the contract

Synonyms of complexity

• complexness
• sophistication
• intricacy
• elaborateness

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.

Recent Examples on the Web

That size and complexity do present an obstacle to the company’s growth. — Justin Birnbaum, Sportico.com, 10 Aug. 2026

Each one a genuine step forward at the time, each one eventually outpaced by the complexity of what enterprises actually needed. — Sid Banerjee, Forbes.com, 10 Aug. 2026

Cori navigates the complexities of growing up in a small town with men who limit her, a mother who can’t protect her, and her dream of becoming a writer. — Matt Grobar, Deadline, 10 Aug. 2026

Historical background The complexities of Pennsylvania’s system of municipalities go back to its foundation as a colony in the 17th century. — Scott Spires, Encyclopedia Britannica, 10 Aug. 2026

Word History

Etymology

complex entry 2 + -ity, perhaps after French complexité

First Known Use

1661, in the meaning defined at sense 1

Rhymes for complexity

• convexity
• perplexity

Kids Definition

complexity

noun

com·​plex·​i·​ty kəm-ˈplek-sət-ē 

käm-

plural complexities

1

: something complex

the complexities of the English language

2

: the quality or state of being complex