illogical
Americanadjective
adjective
-
characterized by lack of logic; senseless or unreasonable
-
disregarding logical principles
Other Word Forms
Etymology
Origin of illogical
Explanation
When there's no good reason or explanation for something, don't fret; chances are it's illogical — meaning that it has no rational explanation behind it. The word logic has origins in the Greek root logos meaning "reason, idea, or word." But slap the prefix il- in front of it, and suddenly the word reverses its meaning. Illogical? Check out other words with the same prefix, like illegitimate and illegal, and you'll quickly see that the prefixil- in front of a word starting in "l" means "not." Suddenly the meaning of illogical isn't quite so illogical after all, is it?
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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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.
Sources close to the player felt it was illogical to think a club would come in and offer more than Barcelona would have had to pay.
From BBC ● Jul. 20, 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
The committee was brusque, thorough, and relentless in rooting out inaccuracies, inconsistencies, incomprehensible statements, and illogical conclusions obscured by technical gibberish.
From "Hidden Figures" by Margot Lee Shetterly
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
