Watermelons are technically classified as a modified form of a berry which is also known as a â€œpepoâ€. It falls under this particular classification because its ovary is fleshy and juicy which are the two defining characteristics of a berry. As far as berries are concerned, the outside of them can be either hard or soft and almost leathery with watermelons being the latter.
Another reason why watermelons are classified as berries is because they have seeds in them with an outer flesh that is completely edible and no core whatsoever.
Many different fruits and vegetables are technically classified as berries, including bananas, tomatoes, and papaya.