trefoil

名词 trefoil:

1. any of several Old World herbs of the genus Medicago having small flowers and trifoliate compound leaves
   同义词：medic, medick
2. a plant of the genus Trifolium
   同义词：clover
3. an architectural ornament in the form of three arcs arranged in a circle

1. A black figure shaped like a trefoil or clover leaf on certain playing cards.
   梅花某些游戏纸牌上的一种黑色图案，类似三叶形或苜蓿叶形