logical

1 according to the rules of logic the lawyer won the case with a logical argument about the motives of the suspect 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

2 based on sound reasoning or information that's the logical choice under the circumstances Synonyms commonsense, commonsensible, commonsensical, firm, hard, informed, just, justified, levelheaded, good, rational, reasonable, reasoned, sensible, sober, solid, valid, well-foundedRelated Words actual, real, true; certain, sure; certified, validated, verified; confirmed, corroborated, substantiated; cogent, convincing; colorable, credible, plausibleNear Antonyms unsubstantiated, unsupported, unwarranted; flimsy, implausible, unconvincing, weak; fallacious, false, misguided, misledAntonyms groundless, illogical, invalid, irrational, nonrational, nonsensical, nonvalid, unfounded, uninformed, unjustified, unreasonable, unreasoned, unsound