costmary
noun
cost·mary ˈkȯst-ˌmer-ē 
ˈkäst-
plural costmaries
: an aromatic composite Eurasian herb (Chrysanthemum balsamita synonym Tanacetum balsamita) having leaves used as a potherb and in flavoring
Word History
Etymology
Middle English costmarie, from coste costmary (from Old English cost, from Latin costum, from Greek kostos, a fragrant root) + Marie the Virgin Mary
First Known Use
15th century, in the meaning defined above