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

The retailer said in a recent statement that its supply chain, product and engineering teams have developed Proxima, a middle-mile inventory positioning system built specifically for the complexity and scale of Target’s network. — Roy Stephen Canivel, Footwear News, 17 Aug. 2026

Understanding complexity at levels that were unthinkable just a few years ago. — Dana Williams, Forbes.com, 17 Aug. 2026

Often called the world’s first analog computer, the mechanism demonstrated an understanding of mechanical calculation that would not appear again at a comparable level of complexity for centuries. — Atharva Gosavi, Interesting Engineering, 16 Aug. 2026

Sexuality and identity become intertwined, while the complexity of a person is reduced to categories that culture, including cinema, repeats. — Callum McLennan, Variety, 14 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