A fruit, in the scientific sense, is the part of a flowering plant that develops from the ovary of a flower and usually contains seeds.

Core idea: what makes a fruit?

  • In botany, a fruit is a mature, ripened ovary of a flowering plant, together with its seeds.
  • After pollination and fertilization, the ovary of the flower grows and changes into a fruit, while the ovules inside become seeds.
  • This means anything that develops from a flower’s ovary and holds seeds counts as a fruit, whether it is sweet, dry, or even hard-shelled.

Why some “vegetables” are actually fruits

  • Tomatoes, cucumbers, peppers, and even bean pods all form from the flower’s ovary and contain seeds, so botanically they are fruits, even though people usually call them vegetables in the kitchen.
  • Nuts (like almonds in their shell) and grains (like corn kernels) also fit the botanical fruit definition because they are ripened ovaries enclosing seeds.

What about taste and cooking use?

  • In everyday language, people often call sweet, juicy plant parts “fruits” and use “vegetable” for savory or less sweet plant parts, regardless of plant anatomy.
  • So botanically a tomato is a fruit, but culinarily it is treated as a vegetable because of its flavor and how it is used in dishes.

The job of a fruit in nature

  • The main biological function of fruit is to protect seeds and help them spread to new places, for example by being eaten by animals or carried by wind or water.
  • Whether the fruit is fleshy like a peach or dry like a pod or acorn, its structure is shaped by how it helps the plant disperse its seeds.

Types of fruits (briefly)

  • Simple fruits : develop from a single ovary in one flower, like peaches and tomatoes.
  • Aggregate fruits : form from many ovaries in one flower, like strawberries and blackberries.
  • Multiple fruits : develop from many flowers whose ovaries merge, like pineapple.

TL;DR: Something is a fruit if it develops from a flower’s ovary and (usually) contains seeds, no matter whether we usually eat it as “fruit” or “vegetable.”

Information gathered from public forums or data available on the internet and portrayed here.