Fruits:

he term fruit has different meanings dependent on context, and the term is not synonymous in food preparation and biology. In botany, which is the scientific study of plants, fruits are the ripened ovaries of flowering plants. In many plant species, the fruit includes the ripened ovary and surrounding tissues. Fruits are the means by which flowering plants disseminate seeds, and the presence of seeds indicates that a structure is most likely a fruit, though not all seeds come from fruits.[1]
No single terminology really fits the enormous variety that is found among plant fruits.[2] The term 'false fruit' (pseudocarp, accessory fruit) is sometimes applied to a fruit like the fig (a multiple-accessory fruit; see below) or to a plant structure that resembles a fruit but is not derived from a flower or flowers. Some gymnosperms, such as yew, have fleshy arils that resemble fruits and some junipers have berry-like, fleshy cones. The term "fruit" has also been inaccurately applied to the seed-containing female cones of many conifers.[3]
Many true fruits, in a botanical sense, are treated as vegetables in cooking and food preparation because they are not sweet. These botanical fruits include cucurbits (e.g., squash, pumpkin, and cucumber), tomatoes, peas, beans, corn, eggplant, and sweet pepper; some spices, such as allspice and chilies, are botanical fruits.[4] Occasionally, though rarely, a culinary "fruit" is not a true fruit in the botanical sense.
For example, rhubarb is often referred to as a fruit, because it is used to make sweet desserts such as pies, though only the petiole of the rhubarb plant is edible.[5] In the culinary sense, a fruit is usually any sweet tasting plant product associated with seed(s), a vegetable is any savoury or less sweet plant product, and a nut any hard, oily, and shelled plant product.[6]