Rosemary, is a woody, perennial herb with fragrant, evergreen, needle-like leaves and white, pink, purple, or blue flowers, native to the Mediterranean region. Rosemary is used as a decorative plant in gardens where it may have pest control effects. The leaves are used to flavor various foods, such as stuffing and roast meats.

Rosemary leaves are used as a flavoring in foods, such as stuffing and roasting lamb, pork, chicken, and turkey. Fresh or dried leaves are used in traditional Mediterranean cuisine. They have a bitter, astringent taste and a characteristic aroma which complements many cooked foods. Herbal tea can be made from the leaves. When roasted with meats or vegetables, the leaves impart a mustard-like aroma with an additional fragrance of charred wood that goes well with barbecued foods.

In amounts typically used to flavor foods, such as one teaspoon (1 gram), rosemary provides no nutritional value. Rosemary extract has been shown to improve the shelf life and heat stability of omega 3–rich oils that are prone to rancidity.

The plant or its oil has been used in folk medicine in the belief it may have medicinal effects. Rosemary was considered sacred to ancient Egyptians, Romans, and Greeks.