Basil, (Ocimum basilicum), also called sweet basil, annual herb of the mint family (Lamiaceae), grown for its aromatic leaves. Basil is likely native to India and is widely grown as a kitchen herb. The leaves are used fresh or dried to flavour meats, fish, salads, and sauces; basil tea is a stimulant.

Basil leaves are glossy and oval-shaped, with smooth or slightly toothed edges that typically cup slightly; the leaves are arranged oppositely along the square stems. The small flowers are borne in terminal clusters and range in colour from white to magenta. The plant is extremely frost-sensitive and grows best in warm climates. Basil is susceptible to Fusarium wilt, blight, and downy mildew, especially when grown in humid conditions.