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unsubstantiated

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adjective un·sub·stan·ti·at·ed \ˌən-səb-ˈstan(t)-shē-ˌā-təd\

Definition of unsubstantiated

  1. :  not proven to be true :  not substantiated an unsubstantiated rumor/report a plausible but unsubstantiated theory

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First Known Use of unsubstantiated

circa 1775

unsubstantiated Synonyms

Synonyms
baseless, foundationless, invalid, nonvalid, unfounded, unreasonable, groundless, unsupported, unwarranted
Antonyms
good, hard, just, justified, reasonable, reasoned, substantiated, valid, well-founded, well-grounded
Related 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, sound

Learn More about unsubstantiated

  1. Thesaurus: All synonyms and antonyms for unsubstantiated Spanish Central: Translation of unsubstantiated Nglish: Translation of unsubstantiated for Spanish speakers

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