The Hogwarts Potions Professor was Severus Snape, a 5-letter name. He was a half-blood wizard who served as Potions Master at Hogwarts School of Witchcraft and Wizardry and was also the Defence Against the Dark Arts professor. Snape was known for his cold and sardonic personality and was deeply loyal to the Dark Lord, Voldemort. He was also a member of the Order of the Phoenix and a double agent working against Voldemort.