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

Almost always the topic assumes a Western liberal-democratic definition of rational, which makes the question pointless.

From The Wall Street Journal • Jun. 5, 2026

The idea that valuing this in a rational way for tax purposes is somehow too hard is an insult to our intelligence.

From MarketWatch • Jun. 5, 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

“It’s not a black hole,” another kid was explaining, sounding perfectly rational.

From "Found" by Margaret Peterson Haddix

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