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.

In that sense, “The Rise and Fall of Rational Control” is an exercise in the liberal education that was already threatened when Mr. Mansfield began teaching History of Modern Political Philosophy in the 1960s.

From The Wall Street Journal • Jan. 30, 2026

Joe Tigay, portfolio manager of the Rational Equity Armor Fund, sees gold in an even more troubling light.

From Barron's • Oct. 22, 2025

Rational thought has apparently left the building – and probably did so right after Elvis did.

From Salon • Aug. 1, 2024

Rational thought, he said, is without a platform.

From Seattle Times • Oct. 4, 2023

"Thus you discover the Rational Potential," Dr. Kramer smiled.

From The Instant of Now by Cox, Irving E.

Vocabulary lists containing rational

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