irrational

[ih-rash-uh-nl, -rash-nl] / ɪˈræʃ ə nl, -ˈræʃ nl /

ADJECTIVE

illogical, senseless

Synonyms

STRONGEST

aberrant absurd crazy foolish incoherent insane preposterous ridiculous stupid unreasonable unsound unwise wrong

STRONG

invalid loony raving silly wild

WEAK

brainless cockamamie delirious demented disconnected disjointed distraught fallacious flaky freaky injudicious kooky mad mindless nonsensical nutty off-the-wall reasonless sophistic specious unreasoning unstable unthinking wacky

Antonyms

STRONGEST

balanced logical rational realistic reasonable responsible sane sensible serious smart sound thoughtful well wise

WEAK

reflective stable

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.

Reading a review … it’s something rational that is describing something irrational.

From Los Angeles Times • May 26, 2026

“I think that irrational exuberance that we saw in the dot com era … is just window dressing to cloak what, to me, is normalizing an addictive behavior in our society,” he said.

From MarketWatch • May 19, 2026

Quantum mania has become a staple of the tech sector, dismissed by some as irrational exuberance.

From Barron's • May 6, 2026

In their legal claim, the group alleges that Vodafone – which has more than 350 franchise stores – made business decisions in "irrational, arbitrary" ways.

From BBC • May 5, 2026

Mom is irrational when she thinks you're in any way criticizing her.

From "Starfish" by Akemi Dawn Bowman

Vocabulary lists containing irrational

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