'Salad' is really a general category. Sometimes salad refers to mixed fruit or lettuces while other times salad can mean pasta tossed with veggies. In this recipe, watermelon salad is is really refers to lettuces, veggies, and fruit. That is, the watermelon is tossed with tomatoes and greens in a tasty vinaigrette dressing to make a watermelon salad.