The name Death Blossom is referring to the Rafflesia Arnoldii, also nicknamed 'corpse flower'. It's an endangered endo-parasitic plant that lives inside a specific species of vine, and produces the world's largest flower. This flower can span a meter across, and smells and looks like rotting flesh. See also: Even More Gullible's Travels
Death Blossom is also a term used in the 1984 movie "The Last Starfighter" in which a fighter pilot fires all weapons indiscriminately in every direction, but the name aside it shares no common elements with the ingame weaponskill.