nonvalid

1 having no basis in reason or fact a nonvalid theory that most scientists rejected long ago Synonyms baseless, foundationless, invalid, groundless, unfounded, unreasonable, unsubstantiated, unsupported, unwarrantedRelated Words illogical, irrational, nonlogical, unconscionable, unsound; fallacious, false, misled, wrong; gratuitous, uncalled-for, unnecessary; flimsy, implausible, misleading, specious, unconvincing, untenable, weak; ill-advised, unreasoned; inconsistent; absurd, asinine, brainless, crackpot, crazy, fatuous, foolish, half-witted, harebrained, meaningless, nonsensical, preposterous, senseless, silly, simpleminded, stupid, unwise; insane, lunatic, mad, nutty, wacky (also whacky)Near Antonyms certified, validated, verified; confirmed, corroborated; informed, logical, rational; commonsense, sane, sensible, sober, wise; actual, genuine, real, true; certain, sure; clear, cogent, compelling, convincing, credible, persuasive, plausible, satisfying, solid, soundAntonyms good, hard, just, justified, reasonable, reasoned, substantiated, valid, well-founded, well-grounded

2 having no legal or binding force failure to inform the suspect of his rights rendered his confession nonvalid Synonyms bad, inoperative, invalid, nonbinding, null, nugatory, null and void, voidRelated Words illegal; useless, worthless; ineffective, ineffectualNear Antonyms legal; workingAntonyms binding, good, valid