wolfsbane (n.) Look up wolfsbane at Dictionary.com
"aconite" (especially Aconitum lycoctonum), a somewhat poisonous plant, 1540s, from wolf + bane; a translation of Latin lycoctonum, from Greek lykotonon, from lykos "wolf" + base of kteinein "to kill." Also known dialectally as badger's bane, hare's bane, bear's bane.