hellebore (n.)

late 14c., from Old French ellebore, from Latin elleborus, from Greek helleboros, the name given to various plants of both poisonous and medicinal qualities, reputed to cure madness; of uncertain origin. Perhaps literally "plant eaten by fawns," from Greek ellos/hellos "fawn" (from PIE *elno-, extended form of *el- (2) "red, brown," in animal and tree names; see elk) + bora "food of beasts," from bibroskein "to eat" (from PIE root *gwora- "food, devouring"). But Beekes writes, "The traditional etymology seems very doubtful; the word could well be non-IE, i.e. Pre-Greek." Related: Helleboric; helleboraceous.