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

According to China's Cyberspace Administration, the campaign's goal was to address negativity and "create a more civilised and rational online environment".

From BBC • Jun. 5, 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

I caught the bug not by reading code but by noticing that the output didn’t match how a rational retiree should behave.

From The Wall Street Journal • May 31, 2026

Besides, the black elite had always wrung concessions from the white power structure—slowly but surely—through back-channel meetings, arguing their case in a dignified, rational, and, above all, civil manner.

From "The Best of Enemies" by Osha Gray Davidson

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