In a mixing bowl, combine the tuna, mayonnaise, red onion, celery, dill, salt, and black pepper. Mix well.
Lay out the tortillas and divide the tuna mixture evenly among them. Spread the mixture evenly across each tortilla.
Top each tortilla with shredded lettuce, sliced cucumber, black olives, and crumbled feta cheese.
Roll up the tortillas tightly, tucking in the sides as you go.
Slice the wraps in half and serve immediately.