Did you know watermelons and bananas are berries?

Yes, watermelons and bananas are berries. I will bet 90 percent of you didn't know until now.
What kind of fruits do we normally consider berries? "Small roundish juicy fruit with no stone".
True, watermelons and other fruits fit this description, but watermelons are not small, and bananas are not round.
So how should a berry be defined? “Fleshy fruit produced from a single ovary.”
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