Cōst'ma-ry, n.

n. [Lat. costum, costus, Gr. κόστος, an Oriental aromatic plant, Ar. kost, kust, Skr. kuschtha, and Maria, Mary.] (Bot.) A species of Balsamita (B. vulgaris), having a strong balsamic smell, and nearly allied to tansy; —called also ale-cost. London.