A fruit is actually the sweet, ripened ovary or ovaries of a seed-bearing plant. A vegetable, in contrast, is an herbaceous plant cultivated for an edible part (seeds, roots, stems, leaves, bulbs, tubers, or non sweet fruits). So, to be really nitpick, a fruit could be a vegetable, but a vegetable could not be a fruit. An interesting list of fruits that are often thought to be vegetables: tomatoes, cucumbers, zucchini, avocados, green, red, and yellow peppers, pea pods and pumpkins.