What is the Draught of Living Death?
It’s a potion that puts the person who drinks it into a deep slumber. If you mix int inocrrectly, it could put the person into an IRREVERSIBLE sleep. The two ingredients are asphodel and wormwood. “For you information, Potter, asphodel and wormwood make a sleeping potion so powerful, it is known as the Draught of Living Death.” Snape, p103 of Philospher’s Stone. Draught means Potion, and Living Death means sleep. When you sleep, you are dead because you aren’t doing anything, but you are still living.