Lavender oil. View of a bottle of lavender oil containing lavender flowers. Lavender (Lavandula spica) oil is extensively used in aromatherapy and herbal medicine. Aromatherapy is a branch of alternative medicine using essential oils extracted from plants. Oils are either applied in small quantities through massage, or they are inhaled, or incorporated into creams. They may also be used in an oil burner to permeate a room with their smell. The oil is also used in perfumes, and has antiseptic, anti-spasmodic and insecticidal properties.