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

Most of the redesign projects Menabóh takes on cost between €300 and €1,000, depending on the complexity of the craftmanship, but some sit beyond this range. — Bella Webb, Vogue, 5 Nov. 2026

And ultimately, Glover believes the greatest wonder isn't the moon, the stars, or even the incredible complexity of nature. — Daisy Dobrijevic, Space.com, 5 Nov. 2026

Elsewhere, there’s no sympathy for the complexity of the challenge facing the American and Israeli strategists who instigated the conflict. — Ishaan Tharoor, New Yorker, 5 Nov. 2026

The tricky job of understanding the desires and habits of an always-evolving consumer has taken on new complexity since the advent of artificial intelligence. — Evan Clark, Footwear News, 5 Nov. 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