real genuine improbable obscure ulterior unlikely vague actual factual concrete proven certain established truthful known definite simple objective material ignorant physical illogical confirmed sure valid supported attested true reliable proved substantiated reasonable justified good reasoned hard just categorical measured calculated undeniable corroborated demonstrated recognized recognised verified sustained upheld establishable authentic tested demonstrable undoubted positive dependable conclusive tried certified trustworthy stated verifiable doubtful dubious questionable impossible inconceivable unreasonable implausible unconvincing unbelievable unthinkable debatable weak unimaginable unsubstantial flimsy impracticable iffy slim incredible literal honest dinkum sincere absolute creditable bonafide unquestionable unfeigned indisputable legit credible legitimate veritable indubitable undisputed expressed explained explicit spoken