In botany, a drupe (or stone fruit) is an indehiscent fruit in which an outer fleshy part (exocarp, or skin; and mesocarp, or flesh) surrounds a shell (the pit, stone, or pyrene) of hardened endocarp with a seed (kernel) inside. These fruits usually develop from a single carpel, and mostly from flowers with superior ovaries (polypyrenous drupes are exceptions). The definitive characteristic of a drupe is that the hard, "lignified" stone (or pit) is derived from the ovary wall of the flower—in an aggregate fruit composed of small, individual drupes (such as a raspberry), each individual is termed a drupelet and may together form a botanic berry.