- the dried, unexpanded flower heads of a wormwood, Artemisia cina(Levant wormseed ), or the fruit of certain goosefoots, especially Chenopodium anthelminticum (or C. ambrosioides), the Mexican tea or American wormseed, used as an anthelmintic drug.
- any of these plants.
- any of various plants having seeds or other parts used in medicine to treat worm infestation, esp an American chenopodiaceous plant, Chenopodium anthelminticum (or C. ambrosioides) (American wormseed), and the santonica plant
- the part of any of these plants that is used as an anthelmintic
