the time when somebody/something had most power or success, or was most popular synonym prime最为强大(或成功、繁荣)的时期 In its heyday, the company ran trains every fifteen minutes. 公司在最兴隆时期每隔十五分钟就开出一列火车。 a fine example from the heyday of Italian cinema 意大利电影业全盛期的一部优秀代表作 a picture of Brigitte Bardot in her heyday 碧姬 · 芭铎事业鼎盛时的一张照片
Word Originlate 16th cent. (denoting good spirits or passion): from archaic heyday!, an exclamation of joy, surprise, etc.