Amalek: A demonic being named in the collection of Jewish lore known as the Zohar. According to this text, Amalek is the greatest impurity. He is credited with the ability to poison a person so thoroughly that he can bring about the death of the soul. In the Zohar, Amalek is equated to the fallen angel Samael. Although identified as separate entities, they are nevertheless presented as being the same essential being. Notably, Samael's name is sometimes translated as “poison of God.”
SOURCE:
The Dictionary of Demons written by Michelle Belanger