yar·row /ˈjær(ˌ)o/
  西洋蓍草
  Yar·row n.  Bot. An American and European composite plant (Achillea Millefolium) with very finely dissected leaves and small white corymbed flowers. It has a strong, and somewhat aromatic, odor and taste, and is sometimes used in making beer, or is dried for smoking. Called also milfoil, and nosebleed.
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  yarrow
       n : ubiquitous strong-scented mat-forming Eurasian herb of
           wasteland, hedgerow or pasture having narrow serrate
           leaves and small usually white florets; widely
           naturalized in North America [syn: milfoil, Achillea
           millefolium]