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Showing results for irrational. Search instead for irrationa.
Definitions

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.

While the motives that drive a knight are often human, political, or both, the logic is as miraculous and irrational as a muddy hedge knight crawling out from under a fallen dragon.

From Salon • Feb. 25, 2026

This was an irrational fear, but this was where Shiffrin was at this point.

From The Wall Street Journal • Feb. 18, 2026

Freight was another sector that some analysts said was subjected to irrational AI fears last week.

From MarketWatch • Feb. 17, 2026

In the past week, the home secretary has announced a number of sweeping changes to policing, having described the current structures as "irrational".

From BBC • Jan. 24, 2026

“You know when a man lives alone as much as I do, his mind can go olf on an irrational tangent just because his social world is out of kilter.”

From "East of Eden" by John Steinbeck