"Feather in one's cap" is a colloquialism that means to have achieved something notable or prestigious. Some synonyms for this term include "badge of honor," "laurel," "accomplishment," "trophy," "medal," "award," "distinction," "prize," "honor," "merit," and "achievement." These synonyms all connote a sense of achievement or recognition for a job well done. They also imply a sense of pride and satisfaction that comes with having accomplished something meaningful. Whether it's a personal or professional accomplishment, having a feather in one's cap is a symbol of success and recognition of hard work and dedication.