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

• 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

• formational
• foundational
• gestational
• gradational
• locational
• mutational
• notational
• relational
• rotational
• sensational
• translational
• vibrational