Thesaurus
rational
adjective
Synonyms and Antonyms of RATIONAL
1
having the ability to reason <human beings are rational creatures>
Related Words analytic (or analytical), logical; brainy, cerebral, highbrow, highbrowed, intellectual; cognitional, cognitive, mental; levelheaded, practical, sane, sensible, sober
Near Antonyms brainless, dense, doltish, dopey (also dopy), dorky [slang], dull, dumb, fatuous, half-witted, mindless, obtuse, senseless, slow, stupid, thickheaded; fallacious, groundless, illogical, invalid, nonsensical
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 analytic (or analytical), coherent, consequent, good, rational, reasonable, sensible, sound, valid, well-founded, well-grounded
Related Words a posteriori, a priori, syllogistic; cognitive, empirical (also empiric); defendable, defensible, justifiable, maintainable, supportable, sustainable, tenable
Near Antonyms 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 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 commonsense, commonsensible, commonsensical, firm, hard, informed, just, justified, levelheaded, logical, rational, reasonable, reasoned, sensible, sober, solid, valid, well-founded
Related Words actual, real, true; certain, sure; certified, validated, verified; confirmed, corroborated, substantiated; cogent, convincing; colorable, credible, plausible
Near Antonyms unsubstantiated, unsupported, unwarranted; flimsy, implausible, unconvincing, weak; fallacious, false, misguided, misled
Antonyms groundless, illogical, invalid, irrational, nonrational, nonsensical, nonvalid, unfounded, uninformed, unjustified, unreasonable, unreasoned, unsound
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