Black pepper (Piper nigrum) is a flowering plant in the family Piperaceae, cultivated for its fruit, known as a peppercorn, which is usually dried and used as a spice and seasoning. When fresh and fully mature, the fruit is about 5 mm (0.20 in) in diameter, dark red, and contains a single seed, like all drupes. Peppercorns and the ground pepper derived from them may be described simply as pepper, or more precisely as black pepper (cooked and dried unripe fruit), green pepper (dried unripe fruit), or white pepper (ripe fruit seeds).

Black pepper is a flowering vine, cultivated for its fruit, which is usually dried and used as a spice and seasoning. Black pepper is native to South India and is extensively cultivated there and elsewhere in tropical regions. The pepper plant is a perennial woody vine growing to 4 m in height on supporting trees, poles, or trellises. It is a spreading vine, rooting readily where trailing stems touch the ground. The leaves are alternate, entire, 5-10 cm long and 3-6 cm broad. The flowers are small, produced on pendulous spikes 4-8 cm long at the leaf nodes, the spikes lengthening to 7-15 cm as the fruit matures. The fruit, known as a peppercorn when dried, is a small drupe five millimetres in diameter, dark red when fully mature, containing a single seed. Dried ground pepper is one of the most common spices in European cuisine and its descendants, having been known and prized since antiquity for both its flavour and its use as a medicine. The spiciness of black pepper is due to the chemical piperine.

Black pepper fruits contain an essential oil (comprising beta-bisbolene, camphene, beta-caryophyllene and many other terpenes and sesquiterpenes), up to 9% alkaloids (especially piperine which is responsible for the acrid taste), about 11% protein and small quantities of minerals. They are a pungent, aromatic, warming herb that lowers fever, is antiseptic and improves digestion. Black pepper is regarded as a stimulating expectorant in Western and Ayurvedic medicine, and as a tranquilizing and anti-emetic in Chinese medicine. The seed is used internally to treat indigestion and wind in western herbalism.  In Chinese medicine it is used as a warming herb to treat stomach chills, food poisoning, cholera, dysentery, diarrhoea and vomiting caused by cold.