Prepare all vegetables: slice cucumbers into half-moons, halve tomatoes, thinly slice red onion, and chop dill.
Cut feta cheese into cubes—aim for pieces about ½-inch in size.
In a small bowl or measuring cup, whisk together olive oil, red wine vinegar, lemon juice, minced garlic, oregano, salt, and pepper until well combined.
In a large mixing bowl, combine cucumbers, tomatoes, feta, red onion, and dill.
Pour dressing over the salad ingredients and gently toss until everything is evenly coated.
Let the salad rest at room temperature for 10-15 minutes to allow flavors to meld.
Give the salad one final gentle toss before serving, and taste to adjust seasoning if needed.