1) Baneful 2) Deadly 3) Deadly or sinister 4) Exclusively Saxon word 5) Exclusively Anglo word 6) Harmful, vindictive 7) Maleficent 8) Menacing 9) Ominous 10) Portending evil 11) Sinister 12) Word of purely Anglo origin 13) Word with Anglo-Saxon origins Found on https://www.crosswordclues.com/clue/baleful
Bale'ful (bāl'ful) adjective [ Anglo-Saxon bealoful . See Bale misery.] 1. Full of deadly or pernicious influence; destructive. ' Baleful enemies.' Shak. « Four infernal rivers that disgorge Into the burning lake their baleful streams. Milton... Found on http://www.encyclo.co.uk/webster/B/8