A fruit that grows from just one flower that contains just one ovary, is not an aggregate fruit but a simple fruit.
Not all flowers with multiple ovaries grow into aggregate fruit; the ovaries of some flowers do not become tightly joined together to make a larger fruit.
Aggregate fruits may also be accessory fruits. In accessory fruits, parts of the flower that are not the ovary become juicy and form part of the fruit.
Aggregate fruits include: