illogical

adjective

il·​log·​i·​cal (ˌ)i(l)-ˈlä-ji-kəl 

1

: not observing the principles of logic

an illogical argument

2

: devoid of logic : senseless

illogical policies

illogicality

(ˌ)i(l)-ˌlä-jə-ˈka-lə-tē 

noun

illogically

(ˌ)i(l)-ˈlä-ji-k(ə-)lē 

adverb

illogicalness

(ˌ)i(l)-ˈlä-ji-kəl-nəs 

noun

Synonyms

• fallacious
• illegitimate
• inconsequent
• inconsequential
• invalid
• irrational
• nonrational
• unreasonable
• unreasoning
• unsound
• weak

Examples of illogical in a Sentence

It is illogical to think that things will change on their own.

the illogical claim that playing basketball makes people taller because one sees so many tall players

Recent Examples on the Web

Pike’s stairs, however, are an M.C. Esher–esque illogical maze, full of steep drop-offs and impossible turns. —Rebecca Alter, Vulture, 29 Apr. 2025

Instead—and this has been reported throughout the process of people trying to preorder a Nintendo Switch 2—individuals go through a confusing and seemingly illogical experience. —Callum Booth, Forbes.com, 24 Apr. 2025

Imposing tariffs on barbecues manufactured in China is illogical. —Tim Bajarin, Forbes.com, 14 Apr. 2025

For example, NFTs experienced what might be on the most rapid rises in value followed by a devastating cycle of value destruction, complete with instances of fraud, illogical business models, and speculation. —Sean Stein Smith, Forbes.com, 19 Apr. 2025

Word History

First Known Use

1588, in the meaning defined at sense 1

Rhymes for illogical

• zoological
• aetiological
• anthropological
• archaeological
• axiological
• climatological
• deontological
• dermatological
• eschatological
• etiological
• etymological
• gerontological

Kids Definition

illogical

adjective

il·​log·​i·​cal (ˈ)il-ˈ(l)äj-i-kəl 

: not using or following good reasoning

illogically

-i-k(ə-)lē 

adverb