A vrykolakas (Greek: βρυκόλακας or βρικόλακας, pronounced [vriˈkolakas]), is a harmful undead creature in Greek folklore. Similar terms such as vourkolakas (βουρκόλακας), vourvoulakas (βουρβούλακας), vorvolakas (βορβόλακας), vourvolakas (βουρβόλακας), vourdoulakas (βουρδούλακας) were also used for the creature.
It shares similarities with numerous other legendary creatures, but is generally equated with the vampire of the folklore of the neighbouring Slavic countries. While the two are very similar, a vrykolakas eats flesh, particularly livers, rather than drinking blood, which combined with other factors such as its appearance bring it more in line with the modern concept of a zombie or ghoul.