Greengrass is the surname of a pure-blood wizarding family. They are related to the Malfoy family, and more distantly to the Black and the Lestrange families. The socio-economic status of the Greengrass family is unknown. However, it is most likely they are a very old and wealthy family, belonging to wizarding Britain's privileged upper class, since Draco Malfoy married Astoria Greengrass, and it would be most out-of-character for any member of the Malfoy family to make ties with and/or marry someone they deemed to be of lesser heritage.
- Astoria Malfoy née Greengrass — wife of Draco Malfoy, mother of Scorpius Malfoy
- Daphne Greengrass — Astoria's older sister, she was in Harry Potter's year and Slytherin house at Hogwarts, and was one of Pansy Parkinson's gang.
- The surname Greengrass seems to simply come from the words green and grass, emphasising Slytherin's house colours. This would imply the Greengrass family have been traditionally sorted into Slytherin.