Stone fruits

Stone fruits (or stonefruits or stonefruit), in botany, is a nonscientific term that refers to drupes, fruits in which an outer fleshy part (exocarp, or skin; and mesocarp, or flesh) surrounds a shell (the pit or stone) of hardened endocarp with a seed inside. These fruits develop from a single carpel, most often from flowers with superior ovaries. The definitive characteristic of a drupe is that the hard, lignified stone (or pit) is derived from the ovary wall of the flower.

More specifically, "stone fruit" commonly refers to members of the genus Prunus, which includes plums, cherries, peaches, apricots and nectarines. It is traditionally placed within the rose family Rosaceae as a subfamily, the Amygdaloideae (or Prunoideae), but sometimes placed in its own family, the Prunaceae (or Amygdalaceae).

Peaches, nectarines, plums, apricots, and cherries are all members of the Prunus genus and are therefore closely related. They commonly are referred to as "stone fruits" because the seed is very large and hard.