Add the white wine vinegar, lime zest and juice to a small bowl. Whisk in the olive oil and season with salt and pepper. Add the thinly sliced red onion and let marinate for 5 to 10 minutes as you prepare the rest of the salad.
Add the watermelon, feta, mint, and arugula to a large bowl. Toss with the vinaigrette and serve immediately after dressing.
Recipe courtesy of The Neelys