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.
If one can go with the illogical flow.
From The Wall Street Journal ● Oct. 29, 2026
Taylor acknowledged that some of the police's "decisions made during our investigations can sometimes appear illogical".
From Barron's ● Oct. 27, 2026
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
Although this sequence seems illogical, it is arguably allowed under current accounting rules.
From MarketWatch ● Apr. 27, 2026
I don't want her to think I'm yelling at her, and even if it is completely illogical, I don't want her to be angry with me.
From "Starfish" by Akemi Dawn Bowman
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Get a wordDefinitions 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.
