rationality

American

[rash-uh-nal-i-tee] / ˌræʃ əˈnæl ɪ ti /

noun

plural

rationalities

the state or quality of being rational.
the possession of reason.
agreeableness to reason; reasonableness.
the exercise of reason.
a reasonable view, practice, etc.

Other Word Forms

antirationality noun
nonrationality noun

Etymology

Origin of rationality

First recorded in 1560–70, rationality is from the Late Latin word ratiōnālitās reasonableness. See rational, -ity

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

"These rules lack humanity and rationality, and they oppress us every day."

From Barron's • Jan. 9, 2026

We comfort the comfortable, and we look for hope in norms and in institutions and in rationality.

From Slate • Dec. 17, 2025

It’s the second factor that often keeps takeover bids alive long after the proposed deals lose their economic rationality.

From Los Angeles Times • Dec. 11, 2025

This work challenges long-held assumptions that rationality, defined as forming and updating beliefs based on evidence, belongs only to humans.

From Science Daily • Nov. 16, 2025

“Something is knocking on the doors,” Theodora said in a tone of pure rationality.

From "The Haunting of Hill House" by Shirley Jackson

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023