Definitions

rational

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

ADJECTIVE

realistic; of sound mind

Synonyms

STRONGEST

analytical balanced deliberate enlightened impartial intelligent judicious levelheaded logical lucid normal prudent reasonable sane sensible sober stable thoughtful wise

STRONG

calm cool intellectual knowing objective reasoning sound synthetic thinking

WEAK

all there cerebral circumspect cognitive collected deductive discerning discriminating far-sighted perspicacious philosophic ratiocinative reflective sagacious together well-advised

Antonyms

STRONGEST

careless confused foolish idiotic illogical insane irrational nonsensical senseless stupid thoughtless unbalanced unintelligent unreasonable unstable unsystematic unwise

STRONG

agitated excited

WEAK

ridiculous unrealistic unsound

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.

Today I’m breaking down why I think the market’s meteoric rise is still rational, and how the software sector proves that investors are grounded in reality.

From Barron's • Jun. 8, 2026

It’s possible that the trillions in value created in the past few years are rational and that the AI rally has years to run.

From The Wall Street Journal • Jun. 2, 2026

“This indicates that AI is making software engineers more productive, which in turn means that rational employers will want more of them, not less,” Windsor wrote.

From MarketWatch • Jun. 1, 2026

And the court continues to conduct itself as though Trump is a rational actor who will hear a no as a no.

From Slate • Jun. 1, 2026

If the market had been at all rational it would have blown up long before.

From "The Big Short" by Michael Lewis

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