Nutmeg, the seed of a tropical tree. The tree is also called nutmeg, as is a spice obtained from the seed. The nutmeg tree is also the source of mace, another spice. The tree is grown commercially in Indonesia; Penang Island, Malaysia; and the West Indies. It is an evergreen with thick, darkgreen leaves, and reaches a maximum height of 40 feet (12 m). Fragrant, yellow flowers produce yellow fruit about the size and shape of apricots.

The fruit is picked after it has split open. When the dried fleshy part is removed, a red aril (netlike layer) surrounding a dark-brown nut is revealed. The aril is ground to produce the powdered, delicately flavored mace used in making pickles, mincemeat, and sauces.

The dark-brown shell of the nut contains a light-brown seed, the nutmeg. The seed is dried by air and sunlight for one to two months. When dried, the nutmeg is roughly oval in shape and about one inch (2.5 cm) long. It is hard and has a wrinkled surface. Fragrant oil contained in the veins of the seed gives nutmeg its flavor. The dried seed is ground to produce the seasoning most commonly bought as nutmeg. Nutmeg is used to flavor desserts such as custards, in eggnog, and in cream sauces for vegetables.

Nutmeg and mace oils are used in medicines and as flavorings and perfumes.

The species of nutmeg used for the spice is Myristica fragrans. It belongs to the family Myristicaceae.