groundless Synonyms

baseless unfounded unwarranted idle wild unsupported unprovoked wanton ungrounded unwarrantable untrue unsupportable unsound unreasoned unreasonable undue uncaused uncalled-for toothless unproved unverified without justification without cause untested unsubstantiated unscientific unmeritorious uncorroborated unconvincing unattested strapless unproven unjustifiable untenable ill-founded unjustified unpardonable unconfirmed suppositional superstitious spurious foundationless flimsy fictitious fictional false fallacious expletory erroneous empty