foundationless

having no basis in reason or fact a careful investigation proved that the charges were foundationless Synonyms baseless, groundless, invalid, nonvalid, 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