Why is a corn kernel both a seed and a fruit structure?

A corn kernel is considered both a seed and a fruit because of its unique botanical structure known as a caryopsis.

In botanical terms, a fruit is the ripened ovary of a flowering plant that encloses the seed. While we often think of fruits as fleshy or succulent, they are technically any mature ovary and its associated parts. A seed is the mature ovule containing the plant embryo and nutritive tissue.12

In a corn kernel, the ovary wall is fused to the seed coat, creating a single, dry, one-seeded fruit structure. Because the seed is inseparable from the ripened ovary wall (the fruit layer) without specialized processing, the entire kernel functions as both the protective fruit and the reproductive seed. Therefore, while the kernel contains the seed, the structure itself is classified as a fruit.31