Mudblood-lover

"Well, you know his opinion of Dumbledore – the man’s such a Mudblood-lover..."

- Draco Malfoy on his father's opinion of Albus Dumbledore

"Mudblood-lover" is a disparaging term for a pure- or half-blood wizard or witch who is not prejudiced against Muggle-born wizards and witches. The more commonly used term for such an individual is "blood traitor". Prejudiced pure-bloods look down upon Muggles and Muggle-borns, referring to the latter by the extremely offensive slur "Mudblood".

Draco Malfoy once referred to Albus Dumbledore as a "Mudblood-lover", citing it as the reason that his father originally wanted him to attend Durmstrang Institute instead of Hogwarts School of Witchcraft and Wizardry. Durmstrang was run by former Death Eater Igor Karkaroff and did not admit Muggle-borns as students, unlike Hogwarts.