irrationally

[ih-rash-uh-nl-ee, -rash-nl-]

adverb

1. in a way that is contrary to reason or is not sensible; illogically.

   In firing a highly competent CEO without cause, the Board acted unlawfully, unreasonably, and irrationally.

   Stick to your simple calculation and logic, even when markets are behaving irrationally.

2. in a way that is driven by impulse or instinct rather than reason; without having or being able to use the faculty of reason.

   When a reporter started poking around, the suspect began acting irrationally and took off like a wild animal.

Other Word Forms

• nonirrationally adverb

Word History and Origins

Origin of irrationally¹

First recorded in 1640–50; irrational ( def. ) + -ly ( def. )

Example Sentences

If investors react impulsively, the people who benefit will be the professionals: the hedge funds, proprietary traders, and algorithmic funds who already dominate pre- and postmarket trading and can take advantage of irrationally priced assets.

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But it’s getting harder to deny that the AI trade isn’t looking “irrationally exuberant,” if you will.

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"The rational world is behaving irrationally by giving him this welcome," she said.

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Tom Cross KC, barrister for the two women, told the court that in deciding the clinic should continue to be registered, "the CQC has acted irrationally".

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He's abandoning Ukraine, which he irrationally hates, probably because he associates it with his humiliating first impeachment.

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Related Words

• foolishly www.thesaurus.com
• stupidly www.thesaurus.com
• unreasonably www.thesaurus.com