costmary definition by Webster's New World
Origin: Middle English costmarye ; from cost (; from Old English ; from Classical Latin costum ; from Classical Greek kostos, name of an aromatic plant) plush Marie, (St.) Mary
costmary definition by American Heritage Dictionary
noun pl. cost·mar·ies
Origin: Middle English costmarie : cost, costmary (from Old English, from Latin costum, from Greek kostos, from Sanskrit kuṣṭhaḥ) + marie, Mary, the mother of Jesus.