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rational

adjective

Synonyms and Antonyms of rational

1 having the ability to reason

  • human beings are rational creatures
Synonyms of rational

intelligent, reasonable, reasoning, thinking
Words Related to rational

analytic (or analytical), logical

brainy, cerebral, highbrow, highbrowed, intellectual

cognitional, cognitive, mental

levelheaded, practical, sane, sensible, sober
Near Antonyms of rational

brainless, dense, doltish, dopey (also dopy), dorky [slang], dull, dumb, fatuous, half-witted, mindless, obtuse, senseless, slow, stupid, thickheaded

fallacious, groundless, illogical, invalid, nonsensical
Antonyms of rational

irrational, nonrational, nonthinking, unintelligent, unreasonable, unreasoning, unthinking

2 according to the rules of logic

  • insisted there was a rational explanation for the strange creaking noises and that there were no such things as ghosts
Synonyms of rational

analytic (or analytical), coherent, consequent, good, logical, reasonable, sensible, sound, valid, well-founded, well-grounded
Words Related to rational

a posteriori, a priori, syllogistic

cognitive, empirical (also empiric)

defendable, defensible, justifiable, maintainable, supportable, sustainable, tenable
Near Antonyms of rational

casuistic (or casuistical), eristic (also eristical), fallacious, misleading, sophistic (or sophistical), specious

unarticulated

unscientific

absurd, cockeyed, crazy, daffy, fatuous, half-baked, half-witted, harebrained, insane, loony (also looney), mad, nonsensical, nutty, preposterous, simpleminded, stupid, weak-minded, witless

senseless, thoughtless

uncompelling, unconvincing
Antonyms of rational

illegitimate, illogical, incoherent, inconsequent, inconsequential, invalid, irrational, unreasonable, unsound, weak

3 based on sound reasoning or information

  • betting all of your savings on the lottery is not a rational move
Synonyms of rational

commonsense, commonsensible, commonsensical, firm, good, hard, informed, just, justified, levelheaded, logical, reasonable, reasoned, sensible, sober, solid, valid, well-founded
Words Related to rational

actual, real, true

certain, sure

certified, validated, verified

confirmed, corroborated, substantiated

cogent, convincing

colorable, credible, plausible
Near Antonyms of rational

unsubstantiated, unsupported, unwarranted

flimsy, implausible, unconvincing, weak

fallacious, false, misguided, misled
Antonyms of rational

groundless, illogical, invalid, irrational, nonrational, nonsensical, nonvalid, unfounded, uninformed, unjustified, unreasonable, unreasoned, unsound

Learn More about rational

  1. See words that rhyme with rational Dictionary: Definition of rational Medical Dictionary: Definition of rational Spanish Central: Translation of rational Nglish: Translation of rational for Spanish speakers Britannica English: Translation of rational for Arabic speakers

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