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

Commercial designs would more likely control groups of cells to reduce hardware complexity and cost. — Neetika Walter, Interesting Engineering, 9 Oct. 2026

Generally, meetings happen at least once per year, but the cadence may vary based on complexity and the scope of the engagement. — Kate Dore, Cfp®, Ea,kelli Grant, Cfp®, CNBC, 8 Oct. 2026

Unique Games The unique games conjecture also falls under complexity theory. — Joseph Howlett, Scientific American, 8 Oct. 2026

Justin has written a series that respects and treats with care the complexity of what happened and the public reaction to it. — Joe Otterson, Variety, 8 Oct. 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