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 of illogical

• unreasonable
• irrational
• unreasoning
• illegitimate

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

At a time when antisemitism was sweeping across Europe, this was a decision both courageous and seemingly illogical. —Georg Szalai, HollywoodReporter, 8 Nov. 2025

Scrutinize fine details like hair, fur, or repetitive patterns that may appear unnatural, and inspect for illogical lighting, shadows, or odd background elements. —Matt Emma, USA Today, 3 Nov. 2025

Word also, unfortunately, retains some seemingly illogical features from versions that date back several decades. —PC Magazine, 18 Oct. 2025

The film had transformed from the messy, illogical version I’d first seen into a hilarious, shrewd, contemplative work of art. —Susan Orlean, New Yorker, 11 Oct. 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