nonrational

adjective

non·​ra·​tio·​nal ˌnän-ˈrash-nəl 

-ˈra-shə-nᵊl

1

: not based on, guided by, or employing reason : not rational : irrational

nonrational beliefs

nonrational behavior

… anthropological history exploring such nonrational aspects of society as mating customs and eating habits.

—Gertrude Himmelfarb

2

mathematics : not relating to or being a rational number : irrational

nonrational numbers

Synonyms of nonrational

• irrational
• unreasoning
• unreasonable
• illegitimate

Examples of nonrational in a Sentence

was so upset that he was completely nonrational for a moment

Recent Examples on the Web

Mid-century collective behavior theories considered social movements to be nonrational, spontaneous events occurring during moments of social and cultural breakdown. — The Editors, JSTOR Daily, 10 Sep. 2025

Word History

First Known Use

1859, in the meaning defined at sense 1

Rhymes for nonrational

• binational
• irrational
• subnational
• transnational
• international
• multinational
• supranational
• national
• rational