Word Study
Costmary
CIDE DICTIONARY
Costmary, n. [L. costum an Oriental aromatic plant (Gr. , cf. Ar. kost, kust) + Maria Mary. Cf. Alecost.].
A garden plant (Chrysanthemum Balsamita ) having a strong balsamic smell, and nearly allied to tansy. It is used as a pot herb and salad plant and in flavoring ale and beer. Called also alecost . [1913 Webster]
OXFORD DICTIONARY
Costmary, n. (pl. -ies) an aromatic composite plant, Balsamita major, formerly used in medicine and for flavouring ale.
Etymology
OE cost f. L costum f. Gk kostos f. Arab. kust an aromatic plant + (St) Mary (with whom it was associated in medieval times)
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