Preheat the oven to 400°F (200°C).
In a large bowl, combine ground turkey, breadcrumbs, Parmesan, onion, garlic, oregano, salt, and pepper.
Form the mixture into meatballs, about 1 inch in diameter.
Place the meatballs on a baking sheet lined with parchment paper and drizzle with olive oil.
Bake the meatballs for 20-25 minutes, or until they reach an internal temperature of 165°F (74°C).
While the meatballs are baking, prepare the tzatziki sauce by mixing yogurt, grated cucumber, lemon juice, and dill in a separate bowl.
Serve the meatballs hot, drizzled with tzatziki on top or on the side.