看電視電影時，我們可以看到美國印第安人的特殊裝扮，他們在重要場合喜歡戴一頂飾滿羽毛的帽子——鷹羽冠。鷹羽冠上的羽毛是用鳥類中最兇猛的鷹或雕的尾部長羽做成的。
原始時期， 工具落後， 得到這種羽毛很不容易， 一般都是那些有力量的勇士才能獵得，所以佩戴有羽毛的帽子是勇敢的象徵，慢慢地，人們用"a feather in one’s cap"來比喻一種值得驕傲的榮譽或不凡的成就。
The American Indians used to wear feathers as a sign of bravery. From that comes a feather in one's cap which refers to an honor or a special achievement that a person can be proud of.
看看下面例句：
Mike has graduated from Oxford University at an age younger than his classmates', his father said to him: "It could be a feather in your cap to have graduated from school at such an early age. " 邁克年級以比同齡人較小的年級畢業於牛津大學，他父親對他說：「這個年紀畢業於這樣一所棒的大學，你可以引以為傲了」。
趣味英語：Face the music跟音樂有沒有關係？