n.  公牛  cow 母牛

n. 〔象、鲸等大型动物的〕雄性动物

• take the bull by the horns  挺身面对困难

• like a bull in a china shop 

  笨手笨脚，莽撞冒失

• bull market  牛市

• bear market  熊市

• Nora decided to take the bull by the horns and organize things for herself.

  诺拉决定迎难而上，自己来安排事情。