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

The idea of a place being both isolating and illogical made sense to a cohort of people whose formative years were shaped by lockdown.

From The Wall Street Journal • Jun. 6, 2026

If that sounds illogical, trainer Chad Brown, who will start Emerging Market in a bid to win his first Derby, can explain.

From Los Angeles Times • Apr. 29, 2026

Although this sequence seems illogical, it is arguably allowed under current accounting rules.

From MarketWatch • Apr. 27, 2026

“It is illogical to say he is a misfit just because he chooses to ride a different animal, provided he can carry out his cowboy duties.”

From "Fish in a Tree" by Lynda Mullaly Hunt

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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