Definitions

illogical

[ih-loj-i-kuhl] / ɪˈlɒdʒ ɪ kəl /

ADJECTIVE

not making sense

Synonyms

STRONGEST

absurd false groundless implausible inconsistent incorrect irrational irrelevant preposterous senseless unreasonable unscientific untenable

WEAK

casuistic cockeyed fallacious fatuous faulty hollow inconclusive incongruous inconsequent invalid mad meaningless not following nutty off the wall screwy self-contradictory sophistic sophistical specious spurious unconnected unproved unsound unsubstantial wacky without basis without foundation

Antonyms

STRONGEST

correct logical rational reasonable right sensible true wise

WEAK

meaningful

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Please forgive this exercise in premise-granting, but this is where the theorized plot against Pratt goes from incoherent to illogical.

From Slate • Jun. 9, 2026

Educational AI, he told journalist Taylor Lorenz, generated “false information” or “illogical questions, illogical texts.”

From Salon • Mar. 30, 2026

Huang told a conference in February that the idea that AI will replace software is “the most illogical thing in the world.”

From The Wall Street Journal • Mar. 1, 2026

Elections experts expressed dismay over Johnson’s comments, calling them baseless and illogical.

From Los Angeles Times • Feb. 4, 2026

I gaped at my reckless, illogical best friend.

From "The Science of Breakable Things" by Tae Keller

Vocabulary lists containing illogical

Inside Out & Back Again

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The Devil's Arithmetic

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Way Off: Synonyms for "Wrong"

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