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.

There are many places to point fingers when reckoning with our new, irrational state of affairs.

From Slate • Apr. 26, 2026

One of them, lawyer Seydou Diagne, called the decision to strip Senegal of their title "so blatant, so absurd, so irrational".

From BBC • Mar. 26, 2026

“In view of the current robust demand for AI cloud services, we are not concerned that Tencent’s deeper involvement in the AI cloud market would lead to irrational competition.”

From The Wall Street Journal • Mar. 23, 2026

"The railway is part of the rationalisation of our transport system, especially on the Uganda side, which is irrational and wasteful," the veteran leader told the ceremony.

From Barron's • Mar. 21, 2026

She’d been acting like Beefy with a fever: irrational, angry, immature.

From "Witchlings" by Claribel A. Ortega

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