rationality

noun

ra·​tio·​nal·​i·​ty ˌra-shə-ˈna-lə-tē 

plural rationalities

1

: the quality or state of being rational

2

: the quality or state of being agreeable to reason : reasonableness

3

: a rational opinion, belief, or practice

—usually plural

Examples of rationality in a Sentence

Recent Examples on the Web

And in Nazareth, one of Israel’s largest Arab cities, Awni Zoabi thanked God for a possible return to rationality in a country where extreme rhetoric has increased. — Cara Anna, Los Angeles Times, 28 Oct. 2026

More than anything, what bothered Swift were claims to certainty, of fervency either in religion or rationality. — Literary Hub, 28 Oct. 2026

At least all of that exhibited a malign cunning, a kind of instrumental rationality. — Andrew Koppelman, Chicago Tribune, 27 Oct. 2026

The psychologists Daniel Kahneman and Amos Tversky won a Nobel Prize for pointing out that most of our decisions are not based on rationality. — Shayla Love, Vox, 25 Oct. 2026

Word History

First Known Use

1628, in the meaning defined at sense 1

Phrases Containing rationality

• hyper-rationality

Rhymes for rationality

• abnormality
• cardinality
• commonality
• communality
• cordiality
• corporeality
• criminality
• criticality
• functionality
• generality
• geniality
• hospitality

Kids Definition

rationality

noun

ra·​tio·​nal·​i·​ty ˌrash-ə-ˈnal-ət-ē 

: the quality or state of being rational

Medical Definition

rationality

noun

ra·​tio·​nal·​i·​ty ˌrash-ə-ˈnal-ət-ē 

plural rationalities

1

: the quality or state of being rational

2

: the quality or state of being agreeable to reason