Synonyms and related words :
groundless, inconclusive, indecisive, not following, not proved, unascertained, unattested, unauthenticated, uncertified, unconfirmed, uncorroborated, undemonstrated, undetermined, unestablished, unfixed, unfounded, unproved, unproven, unsettled, unshown, unsupported, unsupported by evidence, unsustained, untested, untried, unvalidated, unverified, without basis, without grounds