(a.) Pertaining to the sibyls; uttered, written, or composed by sibyls; like the productions of sibyls.

Biblical Gospel Mosaic New-Testament Old-Testament apostolic augural auguring bad baleful baneful betraying black bodeful boding canonical dark dire direful disclosing disclosive divinatory doomful dreary evangelic evangelistic evil evil-starred exposing eye-opening fateful fatidic foreboding forecasting foreseeing foretelling forewarning fortunetelling gloomy gospel haruspical ill ill-boding ill-fated ill-omened ill-starred inauspicious inspired lowering mantic menacing of evil portent ominous oracular portending portentous predictional predictive predictory prefigurative prefiguring presageful presaging presignificative presignifying prognostic prognosticative prophetic revealed revealing revelational revelatory scriptural showing sibyllic sibylline sinister somber talkative textual textuary theopneustic threatening unfavorable unfortunate unlucky unpromising unpropitious untoward vaticinal vaticinatory weather-wise