- any composite plant of the genus Arnica, having opposite leaves and yellow flower heads.
- a tincture of the flowers of A. montana, of Europe, and other species of Arnica, formerly used as an external application in sprains and bruises.
- any N temperate or arctic plant of the genus Arnica, typically having yellow flowers: family Asteraceae (composites)
- the tincture of the dried flower heads of any of these plants, esp A. montana, used in treating bruises
