Is tomato a fruit or vegetable? You are probably going to tell me that tomato is a vegetable. I would argue that it is actually a fruit. Why? Ur... I don't know. Seriously! What are fruits? What are vegetables? I googled it and found out there is no standard answers. It is summarised as followings: From The Straight Dope A fruit is the matured ovary of a flower, containing the seed. After fertilization takes place and the embryo (plantlet) has begun to develop, the surrounding ovule becomes the fruit. Yum. I won’t go on about the four types of fruit–simple, aggregate, multiple and accessory–which explain things like berries and pineapples.