The perispèrm, whose term comes from peri and σπέρμα “seed”, in botany is the reserve tissue, also called outer albumen or nocellar albumen, which forms in the nipple on the outside of the embryonic sac. The perisperm is therefore the complex of nutrients that replace the albumen in the seeds of some plants.
Perisperm is present in the seeds of certain plants alone, e.g. in caryophyllids, or together with the endosperm, e.g. in nymphoeps and piperaceae; it can be located outside or on one side of the normal albumen (secondary endosperm).