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.

At the same time, he has insisted that he is “strongly pro-vaccine” and previously advised Rational Vaccines, a controversial organization dedicated to combating the herpes virus.

From Salon • May 7, 2026

“The Rise and Fall of Rational Control,” based on Mr. Mansfield’s signature course, History of Modern Political Philosophy, known as Government 1061, revises his lectures into chapter-length essays.

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, he said, is without a platform.

From Seattle Times • Oct. 4, 2023

Now, on a higher level in another plane, the Vininese were struggling to submerge the Earthmen's second achievement of the Rational Potential.

From The Instant of Now by Cox, Irving E.

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